Clinical Geriatrics - Reviews
Submitted: 2020-11-20
Published: 2021-03-31

Trazodone: a multifunctional antidepressant. Evaluation of its properties and real-world use

University of Siena School of Medicine, Siena, Tuscany, Italy
Medicine and Rehabilitation Department, Istituto Clinico ‘S. Anna’ Hospital, Brescia, Italy
Department of Neurosciences, Sciences NPSRR, University of Padua Medical School, Padua, Italy
National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, ‘G. Mazzini’ Hospital, Teramo, Italy
Ospedale Richiedei, Palazzolo (BR), Italy
Gerontology Unit, Campus Bio Medico University and Teaching Hospital, Rome, Italy
Memory Clinic, Neurology Department, Catholic University of Rome, Italy
Department of Geriatrics, Nuovo Ospedale Civile ‘S. Agostino Estense’, Modena and Reggio Emilia University, Modena, Italy
University of Siena School of Medicine, Siena, Italy
Department of Physiology and Pharmacology University Sapienza of Rome, and IRCCS Neuomed, Pozzilli, Italy
trazodone major depressive disorder neurological disorder geriatric population insomnia


Trazodone is indicated for the treatment of Major Depressive Disorder (MDD), often associated with anxiety, insomnia, agitation, nervousness, or irritability.
The aim of this review was to summarise the pharmacological proper- ties of trazodone in improving depressive symptoms in elderly patients and in patients with neurological comorbidities, for whom secondary depression is often present.
Five different pharmaceutical formulations of trazodone are available: intravenous or intramuscular liquid solution, immediate-release tablets (I.R.), oral drops, prolonged-release tablets (P.R.), and extended-release Contramid® tablets (COAD). The initial dose of trazodone should range from 75 to 100 mg/day. For COAD formulation, the starting recom- mended dose is 150 mg once daily. In elderly patients, trazodone may be administered at very low dosages (25-50 mg/day for I.R. formula- tion, and 50-100 mg for the P.R. or E.R. formulations). The maximum daily dose should not exceed 300 mg/day, split over two administra- tions across the day.
In elderly patients, trazodone has reported excellent results, keeping high-quality standards for safety and tolerability. It can help to improve insomnia and anxiety without resorting to benzodiazepines. In patients with neurological conditions, trazodone helps to treat anxiety-depres- sive symptoms. In patients with Alzheimer’s disease or frontotemporal dementia, trazodone can help to handle behavioural symptoms, also acting as a putative neuroprotective agent.
Trazodone is well tolerated. Somnolence/sedation, dizziness, consti- pation, and blurred vision are common side effects with an incidence slightly greater than 5%. Orthostatic hypotension and headache are relatively common side effects.
The great availability of formulations allows to personalise trazodone administration according to patient profile characteristics.


Trazodone is indicated for the treatment of depression and has been shown efficacious in reducing most symptoms associated with depression 1-3.

The peculiar multifunctional pharmacological profile of trazodone explains its efficacy to improve Major Depressive Disease (MDD), a very heterogeneous condition often associated with anxiety, insomnia, agitation, nervousness, or irritability 2,4-6. To diagnose MDD, an individual must be experiencing five or more symptoms (Tab. I) during the same 2-week period. At least one of the symptoms should be either depressed mood or anhedonia 7.

All DSM criterion symptoms, except depressed mood, comprise at least two sub-symptoms, and three of the criterion symptoms (sleep, weight/appetite, psychomotor) can be met by either increases or decreases. Therefore, up to 16,400 possible symptom profiles can generate a diagnosis of MDD 8. Furthermore, the transdiagnostic determinants and the DSM-5 specifiers (e.g., with anxious distress or with psychotic features) generate a much higher number of clinically relevant profiles 9,10.

Recent studies investigated the efficacy of particular antidepressants in improving symptoms for specific phenotypical profiles, thus showing how the selection of the best drug for a given cluster could be the new personalised approach for depression 11.

In such context, trazodone can represent an efficacious treatment for the geriatric population.

In the elderly population, the risk of depression is high12. In patients with one or more chronic illnesses or disabling conditions, secondary depression can be induced by pharmacological treatments13. Furthermore, depression can aggravate the chronic disease and vice versa could be exacerbated by the chronic disease itself. For example, heart disease and depression can be reciprocally worsened.

Symptoms of depression in the elderly differ from those in the young. Sleep disturbance and agitation may prevail in elderly patients. Other symptoms, as confusion or impaired attention, may be misinterpreted as a neurological disorder (i.e., Alzheimer’s disease).

In patients with neurological conditions, secondary depression is common. Epilepsy, stroke, Parkinson’s disease, and other neurological illnesses reported a high prevalence of secondary depression. Sleep disorder, fatigue, poor concentration, or disturbed appetite are also present. Antidepressants may improve symptoms, quality of life, and overall survival in patients with neurological disorders 14. The aim of this narrative review was to summarise the pharmacological properties of trazodone in elderly patients and patients with neurological comorbidities. Moreover, this work also investigated trazodone efficacy on some specific symptoms as sleep disturbance, anxiety, agitation, and substance abuse. Two case reports were reported.



Trazodone is a Serotonin Receptor Antagonist and Reuptake Inhibitor (SARI) 2 due to its affinity profile for the serotonin reuptake transporter (SERT) and serotonin receptors 15. Trazodone behaves as a potent antagonist of 5-HT2A and 5-HT2B receptors, an antagonist of 5-HT1D, 5-HT2C, a1A, a 2C H1 receptors with moderate affinity, a partial agonist of 5-HT1A receptors, and an inhibitor of SERT (Tab. II). At therapeutic dose, trazodone has no activity at muscarinic cholinergic receptors, dopamine receptors, and dopamine or noradrenaline transporters. Similar to other antidepressants, it inhibits serotonin reuptake 16.

The multi-target profile of trazodone provides the following clinical advantages:

  1. The partial agonist activity at 5-HT1A receptor may facilitate desensitisation of 5-HT1A receptors in serotonergic projecting neurons of the dorsal raphe nucleus, thereby allowing a rapid antidepressant action17 and may contribute to the anxiolytic activity of trazodone, as suggested by preclinical studies 18;
  2. 5-HT2A and 5-HT2C receptor blockade may limit the incidence of sexual dysfunction, usually associated with serotonergic drugs 19;
  3. Antagonism at 5-HT2A, α1A, and H1 receptors confer sedative and hypnotic properties 20,21. Trazodone may treat the symptoms of hypoactive sexual desire disorder and antidepressant-associated sexual dysfunction because of its 5-HT2 antagonism 22-24;
  4. The moderate affinity for 5-HT2C and H1 receptors may limit the risk of weight gain.


To date, at least five different pharmaceutical preparations of trazodone are available in the European Union (E.U.) or USA markets: 1) intravenous or intramuscular liquid solution, 2) immediate-release tablets (I.R.), 3) oral drops, 4) prolonged-release tablets (P.R.), and 5) extended-release Contramid® tablets (COAD).

Some pharmacokinetic parameters (Cmax, Tmax, and elimination half-life t½) could differ according to the drug formulation (Table III). Trazodone is extensively metabolised by CYP-450 3A4. More than 99% of bioavailable trazodone is converted via oxidative cleavage to meta-chlorophenylpiperazine (mCPP), an active metabolite further metabolised by CYP2D6 25. Meta-chlorophenylpiperazine concentrations in vivo range from 1 to 20% of those of the parent drug 26. Thus, the contribution of mCPP to the overall clinical activity is unclear. Trazodone has shown a serum protein binding of 90-95%, resulting in a bloodstream free fraction of 5-10%. Elimination predominantly follows the renal route. Trazodone pharmacokinetics approximates a two-compartment distribution model 20. Because of its hydrophobic features, this compound easily binds to fat tissues and crosses cell membranes 27. The oral bioavailability of trazodone is mostly affected by food. Cmax value increases by 86% when the drug is administered with food 28.



According to EMA guidelines, the initial dose of trazodone should range from 75 to 100 mg/day, administered in a single dose before bedtime. Dosage should be adjusted accordingly to clinical responses, up to 300 mg/day, split over two administrations across the day. Trazodone reaches the steady-state levels in about two days. The recommended starting dose of COAD is 150 mg once daily in adults. The dose may be increased by 75 mg/day every three days (i.e., start 225 mg on Day 4 of therapy). The maximum daily dose should not exceed 300 mg 29.


The availability of different formulations (Table III) ensures the efficacy of trazodone in a wide range of clinical scenarios. For example, the immediate-release (I.R.) formulation (available as tablets or liquid drops) reaches maximum blood levels in about an hour, ensuring rapid effects for symptoms like insomnia 22. The relatively short elimination half-life (6h) reduces the risk of morning drowsiness 30. The prolonged-release (P.R.) formulation is characterised by a film coating, which ensures slow release into the bloodstream. The extended-release (COAD) formulation provides an even more gradual and continuous absorption of the drug into the bloodstream. It allows a simplified once-a-day prescription schedule, thus enhancing adherence, improving tolerability, and avoiding see-sawing blood concentration patterns 30.



Trazodone is clinically useful in elderly patients, including people with agitated behaviour, because of its specific anxiolytic and sleep normalising effect and excellent safety and tolerability 31. In elderly patients, a very low starting dose is recommended, usually no more than 25-50 mg/day for the I.R. formulation or 50-100 mg for the P.R. or E.R. formulations. However, ageing does not significantly impair liver metabolism by CYP3A4, while the reduced renal clearance may increase trazodone blood concentrations 32.

When treating elderly patients, the once-a-day COAD formulation may be the best choice to rapidly reach therapeutic doses while minimising side effects (i.e., orthostatic hypotension). The liquid formulation may be preferred if dysphagia or other difficulties in administration are present. Drops may represent an advantage when small dosage changes are necessary. The rapid peak effect of the I.R. formulations (drops or tablets) also enables appropriate insomnia management. In our experience, most elderly depressed patients improve with doses as low as 100 mg/day. Finally, the dual action of trazodone on anxiety and depression is particularly useful to reduce benzodiazepines, which are burdened by several risks in elderly patients.


Special populations such as depressed elderly patients may also be at high risk of dementia and cognitive impairment, for which depression has been reported as a risk factor or an early harbinger 33. Trazodone helps to treat anxiety-depressive symptoms associated with subcortical dementias, Parkinsonism, and movement or behavioural disorders. It may be efficacious in treating behavioural symptoms of Alzheimer’s disease 34 and frontotemporal dementia 35. Interestingly, trazodone might cause neuroprotection by inhibiting the pancreatic endoplasmic reticulum kinase and eukaryotic initiation factor-2a (PERK/EIF-2a) unfolded protein response pathway 36. Sustained activation of this pathway, which is associated with Alzheimer’s disease, frontotemporal dementia, and other neurodegenerative disorders characterised by protein misfolding 37-39, causes translation repression, with ensuing neurodegeneration 36. This unique property of trazodone suggests that this drug might be particularly valuable for treating depression associated with insomnia in patients with chronic neurodegenerative disorders, particularly in the early phases of neurodegeneration. In neurodegenerative disorders, trazodone behaves as a putative neuroprotective agent because it may promote the secretion of neurotrophic factors from cultured human astrocytes 40.

Furthermore, the absence of anticholinergic effects of trazodone is a further advantage in treating depression associated with Alzheimer’s disease. The use of tricyclic antidepressant drugs and several antipsychotic agents in Alzheimer’s disease is seriously limited by the anticholinergic activity of these drugs, which may further impair cognition 41,42. On the contrary, recent retrospective analysis has reported an association between trazodone treatment and delayed cognitive decline in a sample of patients affected by Alzheimer’s disease43.


Insomnia is a condition that could significantly impact daytime activities because of a change of the sleeping pattern (difficulties with falling and staying asleep or waking too early). While primary insomnia has an unknown aetiology, secondary insomnia is usually induced by psychiatric or physical conditions or some external factors. There is strong evidence about the effectiveness of trazodone in the treatment of both primary and secondary insomnia 44. Trazodone improves sleep mainly by increasing total sleep time, enhancing delta sleep entry, and decreasing the number of night-time awakenings 45. It maintains these qualities in healthy and depressed-insomniac patients 46,47. However, the antidepressant efficacy of trazodone seems unrelated to the severity of insomnia at baseline 2. Roth et al. (2011) observed that a 50 mg dose of trazodone required one week to ameliorate the delta sleep phase, while 100 mg showed a positive effect after 1-2 days 48.


Agitation and behavioural disturbances

Depressed patients can manifest verbal or physical aggressiveness, especially if anxiety symptoms, depressive episodes with mixed features, or comorbid dementia are present 49,50. Conversely, elderly patients with dementia who manifest physical or verbal aggression showed a higher prevalence of depression 51. Trazodone inhibits aggressiveness 52, probably due to its association of a combined serotoninergic antidepressant activity and H1 histamine receptor blockade at low doses (i.e., 50-75 mg/day). Other drugs used to treat aggressive behaviour associated with depression (e.g., benzodiazepines) may cause falls, tolerance, physical dependence, and cognition impairment. Moreover, post-stroke patients often display depressive symptoms with emotional and behavioural changes such as anger, hostility, and impulsivity53. Of note, trazodone showed beneficial effects at 300 mg/die in post-stroke depression 54.

Preclinical findings have hypothesised that trazodone may restrain L-DOPA-induced dyskinesia and psychosis-like behaviours in Parkinson’s disease 55. Trazodone administration was also beneficial in a sample of bipolar inpatients affected by psychomotor agitation 56. Other studies showed a good efficacy of trazodone in patients with agitation57 and antipsychotic-induced akathisia 58.

Depression and anxiety

A large body of evidence supports the value of trazodone for treating generalised anxiety disorder 59 or post-traumatic stress disorder (PTSD) 60. In both conditions, trazodone improved sleep disturbances 5. It may be of particular help in patients with anxiety disorders who are at risk for benzodiazepine abuse 5.

Depression and substance abuse induced sleep disturbance

The reward deficiency syndrome that includes both dysphoric and depressive symptoms may appear after cocaine detoxification. A 9-patient study about X.R. trazodone formulation for the treatment of cocaine withdrawal symptoms has hypothesised that trazodone may improve the reduction of craving and reduce psychological symptoms, although its efficacy to avoid early relapse should be further confirmed 61.

Depression is commonly represented in substance abuse and usually unrecognised. Proper diagnosis of mood disturbance could prevent episodes of relapse and reduce suicide rates in this patient population. It would be necessary for routine clinical practice to recognise if a patient has primary or substance-induced depression to avoid treatment delay 62.

Sleep disturbance is frequent during alcohol withdrawal. A randomised, double-blind placebo-controlled trial showed that low doses of trazodone could improve sleep quality during alcohol withdrawal. However, the effect was lost once trazodone was discontinued 63.


Trazodone is well tolerated in MDD patients 2,22. The most common side effects are somnolence/sedation, dizziness, constipation, blurred vision. The incidence of these side effects is greater than 5% and is double that of placebo 64. Other bothersome or relatively common side effects include orthostatic hypotension and headache 2,22,65. Orthostatic hypotension may be more severe if an antihypertensive agent is associated. In the geriatric population, falls may occur more frequently 66,67.

Priapism is a rare adverse effect, likely due to α-adrenergic receptor blockade 66,68,69. Trazodone should be used with caution to reduce the risk of priapism in patients affected by multiple myeloma, sickle cell anaemia, hypercoagulable states, leukaemia, autonomic nervous system dysfunctions, and anatomical deformation of the penis (e.g., Peyronie’s disease, angulation, or cavernosal fibrosis), or in combination with SSRIs, cocaine, or atypical antipsychotics 2,70.


Orthostatic hypotension and dizziness

Trazodone has an excellent cardiovascular safety profile 71, although mild orthostatic hypotension can occur. Therefore, it is recommended to measure blood pressure before administration and advise the patient to remain seated or in bed for at least 30 minutes after administration and not to change position too quickly.

A recent investigation on a small sample of real-world elderly depressed patients reported no significant associations between QTc variations and trazodone administration 72. Trazodone may also cause dizziness, which is a consequence of α-adrenergic receptor blockage, and usually occurs when large doses of the drug are taken on an empty stomach 65. Due to the inhibition of small muscle contraction, patients may have a subjective feeling of losing balance and dizziness in more severe cases. In such cases, patients should lay down, rest, and avoid rapid movements. Proper hydration is recommendable, avoiding caffeine, nicotine, or alcohol 73.


Trazodone may induce headache. This effect is mediated by the active metabolite, mCPP, which, as opposed to trazodone, acts as an agonist at various serotonin receptors and may also enhance serotonin release 74. Trazodone-induced headaches may not respond to conventional analgesics, and, therefore, can only be managed by suspending the treatment 75.


Sedation during daytime sleepiness is a common adverse effect of trazodone 76. Daytime sleepiness might contribute to fatigue, decreased quality of life, and increased risk of occupational or car accidents 77. Dosage adjustments, change in trazodone formulation (e.g., switching to the I.R. formulation, administered in the evening), and behavioural interventions, such as going to bed early 78, can improve symptomatology.

Gastrointestinal symptoms

Nausea and other gastrointestinal symptoms may occur if the agent is taken at high doses on empty stomach. Thus, taking trazodone with food is recommended 65. For dry mouth, the use of oral lubricating gels, artificial saliva, or chewing gum might help to enhance salivation 79.


Trazodone is a safe drug. Doses of 500 mg per kg are lethal for experimental animals. In contrast, doses as high as 10 g may not cause death in humans 65. High doses of trazodone may seldom cause serotonin syndrome, a life-threatening condition due to serotonin accumulation 80. The most common systems involved in trazodone overdose are respiratory, cardiovascular, nervous, and gastrointestinal systems 81.

At toxic blood concentrations, trazodone may cause prolongation of Q.T. interval and torsade de pointes. Cases of life-threatening cardiac arrhythmias have been reported even at regular doses. Concomitant use of trazodone with drugs known to prolong the Q.T. interval or causing cardiac toxicity should be avoided 2.

Contraindications - warnings

Trazodone should not be used in combination with monoamine oxidase inhibitors (MAOIs). Caution is needed when trazodone is co-administrated with drugs that increase serotonin levels for the potential risk of serotonin syndrome 82.

In patients with liver failure, trazodone should be avoided 83. It should not be used during intoxication with alcohol or hypnotic agents or in patients with myocardial infarction 84.



A 51-year-old woman, divorced, without sons, was diagnosed with multiple sclerosis. Since she lost had her job, she experienced a depressed mood, sleeping problems, apathy, difficulty performing daily activities, and increased appetite. She also complained of anxiety, aggravation, restlessness, muscle tension, poor concentration, and fatigue. Her primary care physician prescribed her clonazepam, which she gradually increased up to 8 mg/day without consulting her doctor. After two years, since she reported depressed mood, severe anxiety, poor concentration, poor memory, increased appetite, and suicidal thoughts, she was hospitalised. X.R. trazodone 150 mg, to be taken before bedtime, was prescribed. Clonazepam was gradually decreased to 6 mg on day 1, 4 mg on day 2, 3 mg on days 3 and 4, 2 mg on days 6 and 7, and 1 mg on days 8 and 9, followed by discontinuation. During hospitalisation, the patient also received intensive psychotherapy. After three days, trazodone was increased to 225 mg, and after another three days, the dose was further increased to 300 mg. She showed a gradual improvement in mood, anxiety, and cognitive functions.

Trazodone was also combined with prolonged-release quetiapine to improve mood and anxiety. Quetiapine was started at 50 mg, to be taken in the morning, and gradually increased up to 200 mg, always to be taken in the morning. Two weeks after discharge from the hospital, the patient complained about moderate daytime sleepiness, which improved after discontinuing quetiapine. COAD trazodone was continued at 300 mg in the evening. Excellent results were reported.


A 75-year-old widow with three sons showed mild attention deficit and difficulty planning actions, abstracting thoughts, and finding words and names for commonly used objects. In the following two years, her condition deteriorated significantly: memory loss, difficulty recognising familiar people and places, disorientation, inability to acquire new information, and a gradual tendency to neglect her hygiene and nutrition were registered. Therefore, she was admitted to an assisted health residence. Later, she experienced apathy, loss of interest, refusal to get out of her bed, reluctance to eat, insomnia, anxiety, depressed mood, crying spells, and pessimistic thoughts. After a thorough assessment, she was diagnosed with depression, comorbid to cognitive impairment. So far, memantine at the dose of 10 mg/day was administered. Later, COAD trazodone 150 mg, half tablet to be taken in the evening, was prescribed. After three days, her insomnia and anxiety improved, and no side-effects were reported. She started to eat again. COAD trazodone was increased to 1 tablet in the evening with a progressive and clear-cut improvement of sleep, anxiety, mood, appetite, and interests. After about five weeks of trazodone treatment, the patient was completely free of depressive symptoms.


Major depressive disorder is a great public health challenge, the leading worldwide cause of disability. The complexity and heterogeneity of this condition have always been the object of clinicians. Many efforts have been made to identify antidepressants and personalised formulations in improving symptoms according to the different patient profiles. There is evidence that a range of depressive patient profiles, including elderly patients and those with underlying neurological conditions, sleep disturbance, agitation, or substance abuse, may benefit from trazodone.

The efficacy, safety, and tolerability of trazodone are widely proven. Different formulations allow personalised treatments, thus improving specific symptoms associated with depression MDD, like insomnia, anxiety, agitation, or nervousness. The COAD formulation offers the advantage of once-a-day administration and the possibility to start with a dose (150 mg) that is already potentially effective for depression, along with a steady, gradual release of the medication in the bloodstream throughout 24 hours. The PR formulation offers the advantage of an evening administration (up to 150 mg) for patients (e.g., those with middle and late awakenings) who need drug exposure during the night and a maximum blood concentration at approximately 4 hours from drug intake. The I.R. formulation offers the advantage of reaching the maximum blood concentration after 1-2 hours, and this is particularly valuable for depressive patients with initial-early insomnia. Intravenous and intramuscular formulations have immediate or quick absorption, respectively. These advantages are particularly useful in patients with depression and psychomotor agitation. Intravenous and intramuscular formulations help patients with poor adherence or inability (e.g., post-surgery) to take oral medications. Trazodone displays a good tolerability profile, with a low risk for weight gain, sexual dysfunction, and anticholinergic effects such as dry mouth, constipation, and urinary retention. Finally, the PERK/EIF-2a pathway inhibition suggests trazodone as a potential neuroprotective activity in chronic neurodegenerative disorders characterised by protein misfolding, such as Alzheimer’s disease, in which comorbid depression complicates the management of patients.

Figures and tables

Depressed mood most of the day
Diminished interest or loss of pleasure in almost all activities most of the day (anhedonia)
Significant weight change or appetite decrease or increase nearly every day
Sleep disturbance (insomnia or hypersomnia)
Psychomotor agitation or retardation nearly every day
Fatigue or loss of energy nearly every day
Feelings of worthlessness nearly every day
Diminished ability to think or concentrate; indecisiveness nearly every day
Recurrent thoughts of death, recurrent suicidal ideation without a specific plan, or a suicide attempt or specific plan for committing suicide
Table I.MDD Symptoms.
Receptor Ki (nM) Effects
SERT 367.3 Antagonist
5-HT1A 118 Partial agonist
5-HT1D 106 Antagonist
5-HT2A 35.8 Antagonist
5-HT2B 78.4 Antagonist
5-HT2C 223.9 Antagonist
α1A 153 Antagonist
α2C 155 Antagonist
H1 220 Antagonist
Table II.Pharmacodynamic profile of trazodone.
Trazodone Formulations Cmax Tmax t1/2 Food interaction
TZIR 50 mg tablets100 mg tablets25 mg/ml drops60 mg/ml drops 1.2-1.6 μg/ml 1 h (1.5 h elderly) 6.6 h(9-11 h at steady state) Slow absorption
TZIV/IM 50 mg/5 mlsolution for injection NA Immediate 6-8-h No effect
TZPR film-coated 75 mg tablets150 mg tablets 0.7-1.2 μg/mL 4 h 12 h No effect
TZCOAD 150 mg tablets300 mg tablets ~ 1.5 mg/L (steady state)2 ± 0.635 μg/mL 7.57± 2.3 h 10 h Increased absorptionAdministration of TZCOAD 300 mg once daily provides equivalent steady-state exposure to, with a lower Cmax than, TZIR 100 mg given 3 times a day. A high-fat meal increases Cmax, but there is no substantial effect on AUC.
Table III.Pharmacokinetics.


  1. Golden RN, Dawkins K, Nicholas L. The American psychiatric publishing textbook of psychopharmacology. American Psychiatric Publishing, Inc.: Washington, D.C.; 2009.
  2. Fagiolini A, Comandini A, Catena Dell’Osso M. Rediscovering trazodone for the treatment of major depressive disorder [published correction appears in CNS Drugs. 2013;27:677]. CNS Drugs. 2012; 26:1033-49. DOI
  3. Stahl SM. Mechanism of action of trazodone: a multifunctional drug. CNS Spectr. 2009; 14:536-46. DOI
  4. Goracci A, Forgione RN, De Giorgi R. Practical guidance for prescribing trazodone extended-release in major depression. Expert Opin Pharmacother. 2016; 17:433-41. DOI
  5. Bossini L, Casolaro I, Koukouna D. Off-label uses of trazodone: a review. Expert Opin Pharmacother. 2012; 13:1707-17. DOI
  6. Bossini L, Coluccia A, Casolaro I. Off-label trazodone prescription: evidence, benefits and risks. Curr Pharm Des. 2015; 21:3343-51. DOI
  7. American Psychiatric Association. Diagnostic and statistical manual of mental disorders. American Psychiatric Association: Washington, DC; 2013.
  8. Fried EI, Nesse RM. Depression is not a consistent syndrome: an investigation of unique symptom patterns in the STAR*D study. J Affect Disord. 2015; 172:96-102. DOI
  9. Park SC, Kim YK. Diagnostic issues of depressive disorders from kraepelinian dualism to the Diagnostic and statistical manual of mental disorders, Fifth Ed. Psychiatry Investig. 2019; 16:636-44. DOI
  10. Fang Y, Wu Z. Advance in diagnosis of depressive disorder. Adv Exp Med Biol. 2019; 1180:179-91. DOI
  11. Chekroud AM, Gueorguieva R, Krumholz HM. Re-evaluating the efficacy and predictability of antidepressant treatments: a symptom clustering approach. JAMA Psychiatry. 2017; 74:370-8. DOI
  12. Publisher Full Text
  13. Publisher Full Text
  14. Bassiony MM. Depression and neurological disorders. Neurosciences. 2009; 14:220-9.
  15. Khouzam HR. A review of trazodone use in psychiatric and medical conditions. Postgrad Med. 2017; 129:140-8. DOI
  16. Liu B, Liu J, Wang M. From serotonin to neuroplasticity: evolvement of theories for major depressive disorder. Front Cell Neurosci. 2017; 11:305. DOI
  17. Montalbano A, Mlinar B, Bonfiglio F. Dual inhibitory action of trazodone on dorsal raphe serotonergic neurons through 5-HT1A receptor partial agonism and α1-adrenoceptor antagonism. PLoS One. 2019; 14:e0222855. DOI
  18. Odagaki Y, Toyoshima R, Yamauchi T. Trazodone and its active metabolite m-chlorophenylpiperazine as partial agonists at 5-HT1A receptors assessed by [35S]GTPgammaS binding. J Psychopharmacol. 2005; 19:235-41. DOI
  19. Serretti A, Chiesa A. Treatment-emergent sexual dysfunction related to antidepressants: a meta-analysis. J Clin Psychopharmacol. 2009; 29:259-66. DOI
  20. Settimo L, Taylor D. Evaluating the dose-dependent mechanism of action of trazodone by estimation of occupancies for different brain neurotransmitter targets. J Psychopharmacol. 2018; 32:96-104. DOI
  21. Camargos EF, Louzada LL, Quintas JL. Trazodone improves sleep parameters in Alzheimer disease patients: a randomised, double-blind, and placebo-controlled study. Am J Geriatr Psychiatry. 2014; 22:1565-74. DOI
  22. Cuomo A, Ballerini A, Bruni AC. Clinical guidance for the use of trazodone in major depressive disorder and concomitant conditions: pharmacology and clinical practice. Riv Psichiatr. 2019; 54:137-49. DOI
  23. Pyke RE. Trazodone in sexual medicine: underused and overdosed?. Sex Med Rev. 2018; 8:206-16. DOI
  24. Chokka PR, Hankey JR. Assessment and management of sexual dysfunction in the context of depression. Ther Adv Psychopharmacol. 2018; 8:13-23. DOI
  25. Rotzinger S, Fang J, Baker G.B. Trazodone is metabolised to m-chlorophenylpiperazine by CYP3A4 from human sources. Drug Metab Dispos. 1998; 26:572-5.
  26. EMCDDA.Publisher Full Text
  27. Schmitt W. General approach for the calculation of tissue to plasma partition coefficients. ToxicolIn Vitro. 2008; 22:457-67. DOI
  28. FDA.Publisher Full Text
  29. FDA.Publisher Full Text
  30. Fagiolini A, Albert U, Ferrando L. A randomised, double-blind study comparing the efficacy and safety of trazodone once-a-day and venlafaxine extended-release for the treatment of patients with major depressive disorder. Int Clin Psychopharmacol. 2020; 35:137-46. DOI
  31. Osváth P. Az időskori depresszió és agitáció korszerű kezelése – a trazodon alkalmazásának lehetőségei [Current treatment of depression and agitation in the elderly – clinical use of trazodone]. Neuropsychopharmacol Hung. 2013; 15:147-55.
  32. Shi S, Klotz U. Age-related changes in pharmacokinetics. Curr Drug Metab. 2011; 12:601-10. DOI
  33. Ganguli M. Depression, cognitive impairment and dementia: why should clinicians care about the web of causation?. Indian J Psychiatry. 2009; 51:S29-34.
  34. López-Pousa S, Garre-Olmo J, Vilalta-Franch J. Trazodone for Alzheimer’s disease: a naturalistic follow-up study. Arch Gerontol Geriatr. 2008; 47:207-15. DOI
  35. Lebert F, Stekke W, Hasenbroekx C. Frontotemporal dementia: a randomised, controlled trial with trazodone. Dement Geriatr Cogn Disord. 2004; 17:355-9. DOI
  36. Halliday M, Radford H, Zents KAM. Repurposed drugs targeting eIF2α-P-mediated translational repression prevent neurodegeneration in mice. Brain. 2017; 140:1768-83. DOI
  37. Hoozemans JJ, van Haastert ES, Eikelenboom P. Activation of the unfolded protein response in Parkinson’s disease. Biochem Biophys Res Commun. 2007; 354:707-11. DOI
  38. Nijholt DA, Nölle A, van Haastert ES. Unfolded protein response activates glycogen synthase kinase-3 via selective lysosomal degradation. Neurobiol Aging. 2013; 34:1759-71. DOI
  39. Stutzbach LD, Xie SX, Naj A.C.. The unfolded protein response is activated in disease-affected brain regions in progressive supranuclear palsy and Alzheimer’s disease. Acta Neuropathol Commun. 2013; 1:31. DOI
  40. Daniele S, Zappelli E, Martini C. Trazodone regulates neurotrophic/growth factors, mitogen-activated protein kinases and lactate release in human primary astrocytes. J Neuroinflammation. 2015; 12:225. DOI
  41. Coupland CAC, Hill T, Dening T. Anticholinergic drug exposure and the risk of dementia: a nested case-control study. JAMA Intern Med. 2019; 179:1084-93. DOI
  42. Gerretsen P, Pollock BG. Drugs with anticholinergic properties: a current perspective on use and safety. Expert Opin Drug Saf. 2011; 10:751-65. DOI
  43. La AL, Walsh CM, Neylan TC. Long-Term Trazodone Use and Cognition: A Potential Therapeutic Role for Slow-Wave Sleep Enhancers. J Alzheimers Dis. 2019; 67(3):911-921. DOI
  44. Jaffer KY, Chang T, Vanle B. Trazodone for insomnia: a systematic review. Innov Clin Neurosci. 2017; 14:24-34.
  45. Burke AD, Goldfarb D, Bollam P. Diagnosing and treating depression in patients with Alzheimer’s disease. Neurol Ther. 2019; 8:325-50. DOI
  46. Camargos EF, Pandolfi MB, Freitas MP. Trazodone for the treatment of sleep disorders in dementia: an open-label, observational and review study. Arq Neuropsiquiatr. 2011; 69:44-9. DOI
  47. Suzuki H, Yamadera H, Nakamura S. Effects of trazodone and imipramine on the biological rhythm: an analysis of sleep EEG and body core temperature. J Nippon Med Sch. 2002; 69:333-41. DOI
  48. Roth AJ, McCall WV, Liguori A. Cognitive, psychomotor and polysomnographic effects of trazodone in primary insomniacs. J Sleep Res. 2011; 20:552-8. DOI
  49. Verdolini N, Perugi G, Samalin L, BRIDGE-II-Mix Study Group. Aggressiveness in depression: a neglected symptom possibly associated with bipolarity and mixed features. Acta Psychiatr Scand. 2017; 136:362-72. DOI
  50. Lyketsos CG, Steele C, Galik E. Physical aggression in dementia patients and its relationship to depression. Am J Psychiatry. 1999; 156:66-71.
  51. Menon AS, Gruber-Baldini AL, Hebel JR. Relationship between aggressive behaviors and depression among nursing home residents with dementia. Int J Geriatr Psychiatry. 2001; 16:139-46.
  52. Saletu-Zyhlarz GM, Anderer P, Arnold O. Confirmation of the neurophysiologically predicted therapeutic effects of trazodone on its target symptoms depression, anxiety and insomnia by postmarketing clinical studies with a controlled-release formulation in depressed outpatients. Neuropsychobiology. 2003; 48:194-208. DOI
  53. Kim JS. Post-stroke mood and emotional disturbances: pharmacological therapy based on mechanisms. J Stroke. 2016; 18:244-55. DOI
  54. Raffaele R, Rampello L, Vecchio I. Trazodone therapy of the post-stroke depression. Arch Gerontol Geriatr. 1996; 22:217-20. DOI
  55. Hamadjida A, Nuara SG, Gourdon JC. Trazodone alleviates both dyskinesia and psychosis in the parkinsonian marmoset model of Parkinson’s disease. J Neural Transm (Vienna). 2018; 125:1355-60. DOI
  56. Ballerio M, Politi P, Crapanzano C. Clinical effectiveness of parenteral trazodone for the management of psychomotor activation in patients with bipolar disorder. Neuro Endocrinol Lett. 2018; 39:205-8.
  57. Glass OM, Hermida AP, Hershenberg R. Considerations and current trends in the management of the geriatric patient on a consultation-liaison service. Curr Psychiatry Rep. 2020; 22:21. DOI
  58. Stryjer R, Rosenzcwaig S, Bar F. Trazodone for the treatment of neuroleptic-induced acute akathisia: a placebo-controlled, double-blind, crossover study. Clin Neuropharmacol. 2010; 33:219-22. DOI
  59. Gale CK. The treatment of generalised anxiety disorder. A systematic review. Panminerva Med. 2002; 44:283-6.
  60. Maher MJ, Rego SA, Asnis GM. Sleep disturbances in patients with post-traumatic stress disorder: epidemiology, impact and approaches to management. CNS Drugs. 2006; 20:567-90.
  61. Maremmani I, Spera V, Maremmani A. Is trazododone contramid useful in inducing patients to refrain from using cocaine after detoxification, so avoiding early relapse?. A case series. Addict Disord Their Treat. 2019; 18:105-12. DOI
  62. Tolliver BK, Anton RF. Assessment and treatment of mood disorders in the context of substance abuse. Dialogues Clin Neurosci. 2015; 17:181-190.
  63. Friedmann PD, Rose JS, Swift R. Trazodone for sleep disturbance after alcohol detoxification: a double-blind, placebo-controlled trial. Alcohol Clin Exp Res. 2008; 32:1652-60. DOI
  64. Full Text
  65. Schatzberg AF, DeBattista C. Schatzberg’s manual of clinical psychopharmacology. American Psychiatric Association Publishing: Washington DC; 2019.
  66. Kaplan BJ, Sadock VA. Kaplan and Sadock’s pocket handbook of clinical psychiatry. Wolters Kluwer: Baltimore (P.A.); 2018.
  67. Farrell B, Shamji S, Ingar N. Reducing fall risk while managing pain and insomnia: addressing polypharmacy in an 81-year-old woman. Can Pharm J (Ott). 2013; 146:335-41. DOI
  68. Saenz de Tejada I, Ware JC, Blanco R. Pathophysiology of prolonged penile erection associated with trazodone use. J Urol. 1991; 145:60-4.
  69. Warner MD, Peabody CA, Whiteford HA. Trazodone and priapism. J Clin Psychiatry. 1987; 48:244-5.
  70. Sood S, James W, Bailon MJ. Priapism associated with atypical antipsychotic medications: a review. Int Clin Psychopharmacol. 2008; 23:9-17. DOI
  71. Alvarez W, Pickworth KK. Safety of antidepressant drugs in the patient with cardiac disease: a review of the literature. Pharmacotherapy. 2003; 23:754-71. DOI
  72. Armstrong SEM, Brown HK, Shorey C. No association between trazodone and corrected-qt prolongation in older adults. J Clin Psychopharmacol. 2019; 39:528-30. DOI
  73. NHS.Publisher Full Text
  74. Maes M, Westenberg H, Van Doolaeghe E. Effects of trazodone and fluoxetine in the treatment of major depression: therapeutic pharmacokinetic and pharmacodynamic interactions through formation of meta-chlorophenylpiperazine. J Clin Psychopharmacol. 1997; 17:358-64.
  75. Chen HC, Tsai SJ. Trazodone-induced severe headache. Psychiatry Clin Neurosci. 2011; 65:681-2. DOI
  76. Jaffer KY, Chang T, Vanle B. Trazodone for Insomnia: a systematic review. Innov Clin Neurosci. 2017; 14:24-34.
  77. Murray B. A practical approach to excessive daytime sleepiness: a focused review. Can Respir J. 2016;2016. DOI
  78. NHS.Publisher Full Text
  79. Daly C. Oral and dental effects of antidepressants. Aust Prescr. 2016; 39:84. DOI
  80. Gaffney RR, Schreibman IR. Serotonin Syndrome in a patient on trazodone and duloxetine who received fentanyl following a percutaneous liver biopsy. Case Rep Gastroenterol. 2015; 9:132-6.
  81. Levine M, Ruha A-M. Rosen’s emergency medicine: concepts and clinical practice. Elsevier: Philadelphia, PA; 2018.
  82. Shin JJ, Saadabadi A. StatPearls [Internet]. StatPearls Publishing: Treasure Island (F.L.); 2020.
  83. Carvalhana S, Oliveira A, Ferreira P. Acute liver failure due to trazodone and diazepam. GE Port J Gastroenterol. 2017; 24:40-2. DOI
  84. Torrino Medica.Publisher Full Text
  85. Friedrich MJ. Depression Is the leading cause of disability around the world. JAMA. 2017; 317:1517. DOI


Alessandro Cuomo

University of Siena School of Medicine, Siena, Tuscany, Italy

Angelo Bianchetti

Medicine and Rehabilitation Department, Istituto Clinico ‘S. Anna’ Hospital, Brescia, Italy

Annachiara Cagnin

Department of Neurosciences, Sciences NPSRR, University of Padua Medical School, Padua, Italy

Domenico De Berardis

National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, ‘G. Mazzini’ Hospital, Teramo, Italy

Ignazio Di Fazio

Ospedale Richiedei, Palazzolo (BR), Italy

Raffaele Antonelli Incalzi

Gerontology Unit, Campus Bio Medico University and Teaching Hospital, Rome, Italy

Camillo Marra

Memory Clinic, Neurology Department, Catholic University of Rome, Italy

Francesca Neviani

Department of Geriatrics, Nuovo Ospedale Civile ‘S. Agostino Estense’, Modena and Reggio Emilia University, Modena, Italy

Pier Francesco Laurenzi

University of Siena School of Medicine, Siena, Italy

Ferdinando Nicoletti

Department of Physiology and Pharmacology University Sapienza of Rome, and IRCCS Neuomed, Pozzilli, Italy



How to Cite

Cuomo, A., Bianchetti, A., Cagnin, A., De Berardis, D., Di Fazio, I., Antonelli Incalzi, R., Marra, C., Neviani, F., Laurenzi, P.F. and Nicoletti, F. 2021. Trazodone: a multifunctional antidepressant. Evaluation of its properties and real-world use. JOURNAL OF GERONTOLOGY AND GERIATRICS. 69, 2 (Mar. 2021), 120-129. DOI:
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