Depression Drug Summary

Last updated: 24 June 2025

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Melatonergic Agonist*

Content on this page:

Melatonergic Agonist*

Melatonergic Agonist*



Drug Dosage Remarks
Agomelatine Initial dose: 25 mg PO 24 hourly at bedtime
May be increased to 50 mg PO 24 hourly after 2 weeks if no improvement




 Adverse Reactions
  • CNS effects (dizziness, somnolence, insomnia, migraine, headache, anxiety); GI effects (nausea, diarrhea, constipation, upper abdominal pain, elevated liver enzymes); Other effects (back pain, hyperhidrosis, fatigue)
Special Instructions
  • Liver function should be tested before starting Agomelatine and after about 3, 6, 12, & 24 weeks of treatment, and in patients who develop symptoms of hepatic dysfunction
  • Contraindicated in patients with hepatic impairment or liver function tests (LFTs) >3x the upper limit of normal
  • Use with caution in patients with bipolar disorder, history of suicide, diabetes mellitus (DM), obese, alcoholic, moderate-severe renal impairment
  • Not recommended for patients <18 years of age
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Monoamine Oxidase Inhibitors (MAOIs)*


Drug Dosage Remarks
Irreversible, Nonselective Inhibitors  Adverse Reactions
  • CV effects (orthostatic hypotension, arrhythmias); CNS effects (headache, drowsiness, weakness, fatigue, nervousness, agitation, euphoria, insomnia, convulsion, hyperreflexia, dizziness); GI effects (dry mouth, constipation, nausea/vomiting, dyspepsia); Other effects (edema, sexual dysfunction, muscle tremors, sweating)
  • Side effects are frequent and more severe than other antidepressants
Special Instructions
  • Start with low dose to minimize side effects and titrate upward to desired response
  • Avoid in patients with liver or severe renal disease, cerebrovascular disease or pheochromocytoma
  • Use with caution in patients with CV disease or blood disorders, elderly patients, agitated patients, DM, hyperthyroidism
  • Potentially fatal hypertensive crises may occur if combined with foods containing tyramine (eg cheese, meat or yeast extracts, smoked foods, pickled herrings, broad bean pods, fermented soya products, alcoholic beverages); these foods should be avoided while taking MAOI and for 14 days after discontinuation 
    • RIMA is less likely to cause hypertensive reactions to food because of the reversible type of inhibition
  • Potentially fatal drug interactions occur with sympathomimetics, TCA, SSRI, SNRI, Nefazodone and Trazodone, and may occur up to 14 days after discontinuing MAOI
  • Monitor LFTs, CBC, BP, mental status changes in all patients
  • Taper dose slowly (4 weeks recommended) to prevent withdrawal symptoms of GIT and CNS effects
Isocarboxazid Initial dose: 30 mg/day PO in a single dose or in divided doses
If no response after 4 weeks, may increase dose up to
Max dose: 60 mg/day for 4-6 weeks
Once response is obtained, may decrease dose to
Maintenance dose: 10-20 mg/day
Phenelzine Initial dose: 15 mg PO 8 hourly
If no response after 2 weeks, may increase dose to 15 mg PO 6 hourly
Max dose: 30 mg PO 8 hourly
Once response is obtained, may decrease dose to as low as 
Maintenance dose: 15 mg PO every other day
Tranylcypromine  Initial dose: 10 mg PO 12 hourly (in the morning and afternoon)
If no response after 1 week, may increase afternoon dose to 20 mg PO or give additional dose of 10 mg PO at midday
Max dose: 30-60 mg/day 
Once response is obtained, may decrease dose as low as 
Maintenance dose: 10 mg/day 
Reversible, Selective Inhibitor
Moclobemide Initial dose: 300 mg/day PO divided 8-12 hourly
May increase dose to 600 mg/day based on clinical response
May continue for 4-6 weeks
Maintenance dose: 150 mg/day
 Transdermal
 Selegiline Initial dose: Apply 6 mg/24 hr transdermal patch 24 hourly 
May increase dose based on patient's response by increments of 3mg/24 hr 

Adverse Reactions

  • Application site reaction (irritation, erythema); Dermatologic effects (rash, pruritus, acne vulgaris, diaphoresis); CV effects (orthostatic hypotension, peripheral edema); CNS effects (agitation, amnesia, paresthesia); GI effects (anorexia, diarrhea); Respiratory effects (sinusitis, bronchitis, cough)

Special Instructions

  • Apply on intact skin that is clean, dry & hairless on the upper chest or back, upper thigh or outer surface of the upper arm 
  • Contraindicated in patients with pheochromocytoma
  • Use with caution in patients with dementia, psychosis, tardive dyskinesia or excessive tremor, severe hepatic or renal impairment
  • Patient on doses ≥9 mg/24 hr should restrict/limit tyramine-rich foods intake during & for 2 weeks after treatment discontinuation
* Antidepressant therapy in children, adolescents, and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted. 

Multimodal Serotonin Modulator*



Drug Dosage Remarks
Vortioxetine <65 years old: 10 mg PO 24 hourly
May be increased up to 20 mg PO 24 hourly or decreased to 5 mg PO 24 hourly depending on patient’s response




 Adverse Reactions
  • CNS effect (dizziness); GI effects (nausea/vomiting, diarrhea, constipation); Other effects (decreased appetite, abnormal dreams, generalized pruritus)
Special Instructions
  • Not to be used concomitantly with MAOIs or selective MAO-A inhibitors
  • Use with caution in patients with renal or hepatic impairment, hyponatremia, bleeding abnormalities, history of mania/hypomania
  • Closely monitor patient with history of suicide behavior
  • Discontinue if patient develop seizures or there is an increase in seizure frequency
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Noradrenergic & Specific Serotonergic Antidepressant (NaSSA)*



Drug Dosage Remarks
Mirtazapine Initial dose:
15 mg/day PO as a single dose at night or divided 12 hourly
May increase dose gradually at 1-2 weeks intervals if required up to 45 mg/day PO as a single dose at night or divided 12 hourly
Max dose: 45 mg/day PO





 Adverse Reactions
  • CNS effects (sedation, dizziness, headache, abnormal dreams, akathisia); GI effects (dry mouth, increased appetite, constipation, nausea/vomiting); Other effects (weight gain, increased cholesterol, orthostatic hypotension, exanthema)
  • Rarely, bone marrow depression (agranulocytosis, aplastic anemia, thrombocytopenia), suicidal ideation/behavior, urinary retention, SJS, TEN may occur
  • Sexual dysfunction is generally lower than with SSRIs
Special Instructions
  • Start with low dose to minimize side effects and titrate upward to the desired response
  • Use with caution in patients with seizure disorder, hepatic or renal impairment, CV or cerebrovascular diseases, DM, history of bipolar disorder, angle-closure glaucoma or increased intraocular pressure (IOP), benign prostatic hyperplasia, paralytic ileus, volume depleted patients
  • Contraindicated in patients taking MAOIs and for 14 days after discontinuation
  • Monitor for signs of neutropenia or agranulocytosis (fever, sore throat or other signs of infection), suicidal thoughts/ideation, BP, CBC, serum electrolytes, blood sugar levels
  • Do not stop medication abruptly; taper dose over several weeks
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Noradrenaline Reuptake Inhibitor*



Drug Dosage Remarks
Reboxetine Initial dose:
4-8 mg/day PO divided 12 hourly
May increase dose after 3-4 weeks to 10 mg/day
Max dose: 12 mg/day PO





 Adverse Reactions
  • CNS effects (insomnia, vertigo, dizziness, paresthesia); GI effects (dry mouth, constipation); CV effects (tachycardia, postural hypotension); Other effects (impotence, sweating, urinary retention, hyponatremia)
Special Instructions
  • Start with low dose to minimize side effects and titrate upward to the desired response
  • Use with caution in patients with hepatic and renal impairment, bipolar disorder, benign prostatic hyperplasia, urinary retention, glaucoma and history of epilepsy or cardiac disorders
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Other Agents*



Drug Dosage Remarks
Dextromethorphan/Bupropion  Initial dose: Dextromethorphan 45 mg/Bupropion 105 mg PO 24 hourly
Increase dose to Dextromethorphan 45 mg/Bupropion 105 mg PO 12 hourly after 3 days
Max dose: Dextromethorphan 90 mg/Bupropion 210 mg PO 24 hourly 

Adverse Reactions

  • GI effects (nausea, constipation, diarrhea, xerostomia); CNS effects (dizziness, anxiety, drowsiness, fatigue, headache, insomnia); Other effects (sexual disorder, arthralgia)

Special Instructions

  • Closely monitor patients for any clinical worsening, suicidal behavior or thoughts and unusual changes in behavior
  • Contraindicated in patients with hypersensitivity to Dextromethorphan, Bupropion
Gepirone Initial dose: 18.2 mg PO 24 hourly
May be increased to 36.3 mg PO 24 hourly on day 4, to 54.5 mg PO 24 hourly on day 7 & to 72.6 mg PO 24 hourly on day 14 based on clinical response and tolerance

 Adverse Reactions
  • CNS effects (drowsiness, dizziness, headache, fatigue, insomnia); GI effects (nausea/vomiting, abdominal pain, diarrhea); CV effects (tachycardia, edema); Other effects (weight gain, nasal congestion)
Special Instructions
  • Closely monitor patients for any clinical worsening, suicidal behavior or thoughts and unusual changes in behavior
  • Contraindicated in patients with severe hepatic impairment or prolonged QT interval
  • Must be discontinued for at least 14 days when switching to and from another MAOI
  • May precipitate serotonin syndrome when used together with TCAs
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Selective Serotonin Reuptake Enhancer (SSRE)*



Drug Dosage Remarks
Tianeptine 12.5 mg PO 8 hourly

 Adverse Reactions
  • CNS effects (insomnia, drowsiness, nightmares, vertigo, headache); GI effects (epigastric pain, dry mouth, anorexia, nausea/vomiting, constipation, flatulence); Other effects (tachycardia, lump in throat, respiratory discomfort, fatigue, joint or muscle pain)
Special Instructions
  • Take doses before the main meals of the day
  • Avoid use in patients with history of substance dependence, suicidal behavior, volume-depleted or cirrhotic patients, concomitant use with diuretics, MAOIs or alcohol, children <15 years of age
  • If possible, discontinue medication 24-48 hours prior to general anesthesia
  • Do not stop medication abruptly; taper dose over 7-14 days
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Selective Serotonin Reuptake Inhibitors (SSRIs)*



Drug Dosage Remarks
Citalopram Initial dose: 20 mg PO 24 hourly
May increase dose after 1 week to
Maintenance dose: 40 mg PO 24 hourly
Max dose: 40 mg PO 24 hourly		 Adverse Reactions
  • GI effects (dry mouth, nausea/vomiting, diarrhea, dyspepsia, abdominal pain); CNS effects (insomnia, tremor, somnolence, dizziness, anxiety); Musculoskeletal effects (myalgia, arthralgia); CV effects (palpitation, orthostatic hypotension, hypertension); Respiratory effects (sinusitis, rhinitis); Other effects (sexual dysfunction, sweating, hyponatremia, fatigue)
Special Instructions
  • Initial feeling of increased anxiety may occur with SSRI; therefore, initial dose should be lower than normally prescribed for depression and increased slowly
  • If discontinued after long-term use, taper dose over several weeks
  • Use with caution in patients with hepatic or renal dysfunction, seizure disorders, diabetic patients, long QT syndrome, patients undergoing ECT, patients with bleeding disorder or taking medications that will affect clotting of blood
  • Contraindicated in patients taking MAOIs or within 14 days after discontinuation, QT prolonging drugs, CV disease (decompensated heart failure, recent acute myocardial infarction [MI], bradycardia) children and adolescents <18 years old
  • Monitor suicidal thoughts/behavior, ECG, serum K, Mg, Na, LFTs
Escitalopram Initial dose: 10-20 mg PO 24 hourly
May be increased after 1 week to:
Max dose: 20 mg PO 24 hourly		 Adverse Reactions
  • Adverse effects are usually transient: GI effects (nausea, constipation, diarrhea, decreased appetite); CNS effects (somnolence, dizziness, insomnia, headache, abnormal dreams); Respiratory effects (yawning, sinusitis); Musculoskeletal effects (myalgia, arthralgia); Other effects (sweating, sexual dysfunction, fatigue, pyrexia, increased or decreased appetite)
Special Instructions
  • Same as Citalopram
Fluoxetine Initial dose: 20 mg PO 24 hourly (in the morning)
If no response after several weeks, may increase dose gradually
Max dose:  60 mg PO 24 hourly
Total daily dose >20 mg/day should be divided 12 hourly		 Adverse Reactions
  • Dose related: Nervousness, anxiety, insomnia
  • CNS effects (headache, drowsiness, tremor, dizziness, sensation disturbance, abnormal dreams, mania, insomnia); GI effects (nausea, diarrhea, anorexia); CV effects (palpitations, prolonged QT); Other effects (blurred vision, sexual dysfunction, fatigue, decreased appetite, arthralgia)
Special Instructions
  • Same as Citalopram
Fluvoxamine Initial dose: 50-100 mg PO 24 hourly at bedtime
Adjust dose gradually based on patient response by 50-mg increments every 4-7 days
Usual dose range: 100-200 mg PO 24 hourly
Doses >150 mg/day should be divided 8-12 hourly
Max dose: 300 mg PO 24 hourly		 Adverse Reactions
  • CNS effects (headache, somnolence, insomnia, dizziness, nervousness, tremors); GI effects (nausea/vomiting, diarrhea, constipation, abdominal pain); CV effects (palpitations, tachycardia); Other effects (muscle weakness, sexual dysfunction, urinary retention, yawning)
Special Instructions
  • Same as Citalopram
Paroxetine Immediate-release:
Initial dose:  20 mg PO 24 hourly
May increase dose by 10-mg increments at weekly intervals up to:
Max dose:50 mg/day
Extended-release:
Initial dose: 25 mg PO 24 hourly
May increase by 12.5-mg increments at weekly intervals up to:
Max dose: 62.5 mg PO 24 hourly

 Adverse Reactions
  • Dose-related: Somnolence, asthenia, dizziness, tremor, nausea
  • CNS effects (headache, insomnia, nervousness, anxiety); GI effects (dry mouth, constipation, diarrhea); CV effect (sinus tachycardia); Other effects (sexual dysfunction, oropharyngeal disorders, myopathy)
Special Instructions
  • Same as Citalopram
  • Use with caution in women of childbearing age due to the high rate of fetal toxicity
Sertraline
Initial dose: 50 mg PO 24 hourly
(in the morning)
May increase dose by 50-mg increments at weekly intervals
Usual maintenance dose: 50-100 mg PO 24 hourly
Max dose: 200 mg PO 24 hourly


 Adverse Reactions
  • CNS effects (headache, somnolence, drowsiness, fatigue, dizziness, insomnia, tremor, anxiety, paresthesia, agitation); GI effects (nausea, dry mouth, diarrhea, constipation); CV effects (palpitation, chest pain, QTc prolongation); Musculoskeletal effects (arthralgia, myalgia); Other effects (sexual dysfunction, abnormal vision)
Special Instructions
  • Same as Citalopram
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Serotonin & Norepinephrine Reuptake Inhibitors (SNRIs)*



Drug Dosage Remarks
Desvenlafaxine 50 mg PO 24 hourly
May increase dose gradually after interval of ≥7 days up to:
Max dose: 200 mg/day
 Adverse Reactions
  • Dose-related: Vasodilation, hypertension
  • CNS effects (somnolence, dizziness, insomnia, nervousness, anxiety, yawning, abnormal dreams, tremor); GI effects (nausea/vomiting, xerostomia, weight loss, anorexia, constipation, diarrhea); CV effects (palpitations, tachycardia); Other effects (sexual dysfunction, blurred vision, increased sweating, hot flush)
Special Instructions
  • Start with low dose to minimize side effects and titrate upward to the desired response
  • Use with caution in patients with renal and hepatic impairment, CV, cerebrovascular, seizure, and lipid metabolism disorders, history of mania/hypomania, suicide, narrow-angle glaucoma or increased IOP, predisposed to bleeding or taking medications that can affect blood clotting
  • Contraindicated in patients taking MAOIs or within 14 days after discontinuation
  • Do not stop medication abruptly; taper dose over several weeks
Duloxetine 20 mg PO 12 hourly up to 30 mg PO 12 hourly or
60 mg PO 24 hourly
May increase in increments of 30 mg/day over 1 week
Max dose: 120 mg PO 24 hourly
Levomilnacipran 20 mg PO 24 hourly x 2 days then increase to 40 mg PO 24 hourly
Maintenance dose: 40-120 mg PO 24 hourly
Max dose: 120 mg PO 24 hourly
Milnacipran 50 mg PO 12 hourly
Venlafaxine Immediate release:
75 mg PO 24 hourly in 2-3 divided doses
May increase in increments of up to 75 mg/day at intervals of ≥4 days
Max dose: 375 mg PO 24 hourly
Extended release:
75 mg PO 24 hourly
May increase dose gradually after interval of ≥4 days up to:
Max dose: 225 mg PO 24 hourly
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Serotonin Modulators*



Drug Dosage Remarks
Nefazodone Initial dose: 100 mg PO 12 hourly
May increase dose by 100-200 mg/day divided 12 hourly at weekly intervals
Max dose: 300 mg PO 12 hourly		 Adverse Reactions
  • CNS effects (lightheadedness, dizziness, incoordination, sedation, confusion, memory impairment, suicidal behavior); GI effects (dry mouth, nausea, constipation, rarely hepatotoxicity); CV effects (sinus bradycardia, orthostatic hypotension, palpitation); Other effects (abnormal vision, dyspnea, impotence, asthenia)
  • Trazodone: Drowsiness/sedation that usually decreases with continued treatment, small but serious risk of priapism
Special Instructions
  • Start with low dose to minimize side effects and titrate upward to the desired response
  • Use with caution in patients with seizure disorder, cerebrovascular, CV diseases or history of mania, severe hepatic or renal impairment
  • Trazodone: Discontinue drug immediately if with signs of blood dyscrasia, hepatic impairment or priapism
  • Do not stop medication abruptly; taper dose over several weeks
  • Monitor behavioral changes, LFTs during treatment
Trazodone Initial dose: 150 mg/day PO in a single dose at night or in divided doses
May increase dose at increments of 50 mg every 3-4 days up to 300-400 mg/day
Max dose: 600 mg/day PO in divided doses
Vilazodone
Initial dose: 10 mg PO 24 hourly x 1 week
May increase dose by 20-40 mg/day 24 hourly at weekly intervals
Max dose: 40 mg PO 24 hourly
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Tetracyclic Antidepressants*



Drug Dosage Remarks
Maprotiline Initial dose:75 mg/day PO divided 8 hourly
May increase dose gradually at 25-mg increments every 2 weeks up to:
Severe depression:100-150 mg/day PO
Max dose: 225 mg/day		 Adverse Reactions
  • Maprotiline: Similar to TCA except antimuscarinic effects are less frequent but rashes are more common
  • Mianserin: Similar to TCA except antimuscarinic effects and cardiac side effects are less frequent and less severe; may cause bone marrow depression
Special Instructions
  • Same as TCA
  • Maprotiline: Use with caution in patients with low seizure threshold
Mianserin 30-40 mg/day PO in a single dose at night or in divided doses
May increase dose gradually up to 90 mg/day
Max dose: 200 mg/day PO in divided doses

*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Tricyclic Antidepressants (TCAs)*



Drug Dosage Remarks
Amitriptyline Initial dose: 50-75 mg/day PO in divided doses or 50-100 mg/day PO as a single dose at night
May increase dose at increments of 25-50 mg up to 150-200 mg/day as a single dose at night
Maintenance dose: 50-100 mg/day
Max dose: 300 mg/day in divided doses		 Adverse Reactions
  • Side effects are mostly due to antimuscarinic actions and may be decreased if started at low dose and increased gradually
  • GI effects (dry mouth, constipation may lead to paralytic ileus, nausea/vomiting, gastric irritation); CNS effects (drowsiness, nervousness, insomnia, headache, peripheral neuropathy, ataxia, tremor, confusion/delirium can occur especially in older patients); CV effects (hypotension, tachycardia, palpitation, prolonged QT); Other effects (blurred vision, increased IOP, urinary retention, hyperthermia, sweating, weight gain)
Special Instructions
  • Start with low dose to minimize side effects and titrate upward to the desired response
  • Use with caution in patients with urinary retention, prostatic hyperplasia, chronic constipation, untreated angle-closure glaucoma, patients with CV disease, history of epilepsy, DM, impaired renal or hepatic function, patients undergoing ECT
  • Contraindicated in patients taking MAOIs or within 14 days after discontinuation, recent acute MI, severe liver disease
  • Elderly patients may be sensitive to side effects; lower dose should be used
  • Do not stop medication abruptly; taper dose over several weeks
  • Monitor suicidal ideation or behavior, BP, heart rate, electrocardiogram (ECG), LFTs
Amoxapine Initial dose: 50 mg PO 8-12 hrly
May increase dose to 100 mg PO 8-12 hourly by the end of first week based on response
Max dose: 600 mg PO 24 hourly
Clomipramine Initial dose: 10-25 mg/day PO or 25 mg PO 8-12 hourly
May increase dose gradually up to 30-150 mg/day PO in divided doses or as a single dose at night
Max dose: 250 mg PO 24 hourly
Desipramine Initial dose: 25-50 mg PO 24 hourly or in divided doses
May increase gradually to 25-50 mg/day PO at weekly intervals
Usual maintenance dose: 100-200 mg PO 24 hourly or in divided doses
Max dose: 300 mg PO 24 hourly
Dosulepin
(Dothiepin)		 Initial dose: 75 mg PO 8 hourly for 1-2 weeks
Maintenance dose: 150 mg PO 24 hourly at night
Max dose: 225 mg PO 24 hourly
Doxepin Initial dose: 75 mg PO 24 hourly
May increase dose gradually based on patient response up to:
Max dose: 300 mg PO 24 hourly
Total daily dose >100 mg/day PO should be administered in divided doses
Imipramine Initial dose: 25 mg/day PO 8 hourly or 75 mg PO 24 hourly given as a single bedtime dose or in divided doses
May increase dose gradually up to 50-150 mg/day PO
Max dose: 200 mg PO 24 hourly
Lofepramine 70 mg PO 8-12 hourly
Nortriptyline 25-50 mg PO in 6-8 hourly or 24 hourly at bedtime or
10-25 mg PO 6-12 hourly
May increase dose gradually by 10-25-mg increments every 2-3 days up to:
Max dose: 150 mg PO 24 hourly
Protriptyline Initial dose: 5-10 mg PO 6-8 hourly but not to exceed 40 mg/day
May increase dose in 10-mg increments at weekly intervals
Max dose: 60 mg PO 24 hourly
Trimipramine Initial dose: 50-75 mg/day PO in divided doses
May increase dose gradually up to 150 mg/day PO in divided doses
Maintenance dose: 75-150 mg/day PO
Max dose: 200 mg PO 24 hourly
*Antidepressant therapy in children, adolescents and young adults is associated with clinical worsening, suicidality or unusual changes in behavior. Close observation of the patient and communication with the prescribing physician is warranted.

Other Antidepressant

Drugs Used in Treatment-Resistant Depression

Drug Dosage Remarks
Esketamine Adults <65 years old:
Week 1-4:
Day 1: 56 mg intranasal 24 hourly
Day 2-4: 56 mg or 84 mg intranasally 2 times/week
Week 5-8:
56 mg or 84 mg intranasally once weekly
Week 9 onwards:
56 mg or 84 mg intranasally every 2 weeks or once weekly
Adults ≥65 years old:
Week 1-4:
Day 1: 28 mg intranasal 24 hourly
Day 2-4: 28 mg, 56 mg or 84 mg intranasally 2 times/week
Week 5-8:
28 mg, 56 mg or 84 mg intranasally once weekly
Week 9 onwards:
28 mg, 56 mg or 84 mg intranasally every 2 weeks or once weekly
Dosage change should be in 28 mg increments
 Adverse Reactions
  • CNS effects (dissociation, dizziness, headache, dysgeusia, somnolence, hypoasthesia, vertigo); GI effects (nausea, vomiting); CV effects (tachycardia, hypertension)
Special Instructions
  • Blood pressure (BP) should be assessed before taking Esketamine
  • Contraindicated in patients for whom an increase in blood pressure or intracranial pressure poses a serious risk
  • Use with caution in patients with somnolence, sedation, dissociative symptoms, perception disturbances, dizziness, vertigo and anxiety; clinically significant or unstable CV or respiratory conditions; presence or history of psychosis; presence or history of mania or bipolar disorder; hyperthyroidism that has not been sufficiently treated; history of brain injury, hypertensive encephalopathy, intrathecal therapy with ventricular shunts, or any other condition associated with increased intracranial pressure
  • Avoid concomitant use with CNS depressants that may increase the risk for sedation
  • Closely monitor patients for any clinical worsening, suicidal behavior or thoughts and unusual changes in behavior
  • Individuals with history of drug abuse or dependence may be at greater risk for abuse and misuse

Anticonvulsant

Drugs Used in Augmentation Therapy

Drug Dosage Remarks
Lamotrigine 100-300 mg PO in divided doses Adverse Reactions
  • CV effects (chest pain, edema); CNS effects (dizziness, drowsiness, insomnia, headache, confusion, agitation); GI effects (nausea/vomiting); Other effects (photosensitivity, angioedema, blurred vision, tremor); Hypersensitivity effects (fever, malaise, flu-like symptoms, lymphadenopathy, facial edema, rarely hepatic dysfunction)
  • Skin rashes, including Stevens-Johnson syndrome and toxic epidermal necrolysis
    • Usually occur within 8 weeks of starting therapy
  • Symptoms associated with aseptic meningitis typically occur 1-42 days after starting therapy and resolve upon discontinuation
Special Instructions
  • Use with caution in patients with impaired cardiac function, hepatic or renal impairment
  • Patient should inform doctor immediately if signs of rash, flu-like hypersensitivity symptoms, or signs and symptoms associated with aseptic meningitis develop
  • Monitor for any emergence or worsening of depression, suicidal tendency, unusual changes in mood or behavior

Atypical/2nd Generation Antipsychotics

Drugs Used in Augmentation Therapy
Drug Dosage Remarks
Diazepines, Oxazepines, Thiazepines & Oxepines
Olanzapine Treatment resistant depression:
Initial dose combined w/ Fluoxetine (25 mg): 5 mg PO 24 hourly in the evening		 Adverse Reactions
  • Metabolic effects (weight gain, increased appetite, dyslipidemia, glucose dysregulation); Endocrine effect (mild and transient hyperprolactinemia); CNS effects (somnolence, dizziness, akathisia, parkinsonism, dyskinesia); GI effects (constipation, dry mouth, transient, asymptomatic elevations of hepatic transaminases); CV effect (orthostatic hypotension)
Special Instructions
  • Contraindicated in patients with known risk of narrow-angle glaucoma, concomitant use with MAOIs or within 14 days of its discontinuation
  • Use with caution in hyperglycemia or exacerbation of preexisting diabetes, ketoacidosis, diabetic coma, history of drug-induced bone marrow depression/toxicity; low leukocyte or neutrophil counts, neuroleptic malignant syndrome, seizures, tardive dyskinesia, postural hypotension, in dementia psychosis, long QT syndrome
  • Monitor suicidal behavior, ECG, lipid profile panel
  • Avoid abrupt withdrawal
Quetiapine Daily dose at the start of therapy:
Days 1 & 2: 50 mg PO 24 hourly
Days 3 & 4: 150 mg PO 24 hourly
Day 5: May adjust dose within 50-300 mg/day depending on clinical response and tolerability of the patient
 Adverse Reactions
  • CNS effects (confusion, agitation, somnolence, dizziness, mild asthenia, syncope, neuroleptic malignant syndrome); GI effects (dry mouth, constipation, dyspepsia); CV effects (tachycardia, orthostatic hypotension, palpitation); Other effects (peripheral edema, rhinitis, blurred vision)
Special Instructions
  • Should be administered prior to bedtime
  • Use with caution in combination with centrally acting drugs and alcohol; in patients with CV and cerebrovascular diseases, seizure disorder, conditions predisposing to hypotension, extrapyramidal symptoms and tardive dyskinesia, neuroleptic malignant syndrome, in patients with increased risk of suicidal thoughts, self-harm and suicide-related events

Lithium

Drugs Used in Augmentation Therapy

Drug Dosage Remarks
Lithium Initial dose:  
400-1,200 mg PO 12-24 hourly or
600 mg PO 8 hourly
Individualize dosage according to serum concentration

 Adverse Reactions
  • Fine hand tremor, polyuria, thirst and nausea may occur at initial therapy and usually subside with continued therapy or with dose reduction
  • Metabolic effects (hyperglycemia, hypercalcemia, weight gain, anorexia); Endocrine effects (hypothyroidism, hyperthyroidism, euthyroid goiter, hyperparathyroidism); CNS effects (tremors, fasciculations, ataxia, extrapyramidal symptoms); CV effect (cardiac arrhythmia); GI effects (nausea/vomiting, diarrhea, gastritis, excessive salivation, dry mouth)
Special Instructions
  • Contraindicated in patients with CV disease (ie Brugada syndrome) and significant renal disease, untreated hypothyroidism, Na imbalance resulting from dehydration, Addison’s disease, reduced dietary salt intake, nephrogenic diabetes insipidus
  • Use with caution in electroconvulsive therapy
  • Monitor serum lithium levels ≥2x weekly during acute phase then at least every 2 months during maintenance phase
    • Take blood samples 12 hours after evening dose to measure lithium concentration
  • Gradual withdrawal period of at least 2 weeks
  • Discontinue immediately on the first signs of toxicity
  • Periodically monitor renal function, CBC, serum electrolytes, thyroid function test

Other Antipsychotics

Drugs Used in Augmentation Therapy

Drug Dosage Remarks
Aripiprazole Initial dose: 2-5 mg PO 24 hourly
Dose may be adjusted up to 5 mg PO 24 hourly gradually (at intervals of at least 1 week) Recommended dose: 2-15 mg PO 24 hourly
Max dose: 15 mg PO 24 hourly 		 Adverse Reactions
  • CNS effects (headache, dizziness, akathisia, anxiety, insomnia, restlessness, somnolence, extrapyramidal disorder, sedation, tremor, fatigue); GI effects (nausea/vomiting, constipation); Other effects (salivary hypersecretion, blurred vision, impair core body temperature regulation)
Special Instructions
  • Use with caution in patients with dementia-related psychosis, increased risk of suicidality, in neuroleptic malignant syndrome, tardive dyskinesia, orthostatic hypotension, hyperglycemia, DM, dyslipidemia, seizures/convulsions, dysphagia, known CV or cerebrovascular diseases, renal or hepatic impairment
  • May impair ability to drive or operate machinery
  • Monitor for suicidal ideation or clinical worsening, BP, CBC, fasting blood glucose/HbA1c, fasting lipid profile should be tested at start of therapy then monitored periodically
    • Discontinue if with severe neutropenia (absolute neutrophil count <1000 mm3)
  • Avoid abrupt withdrawal
Brexpiprazole Initial dose: 0.5-1 mg PO 24 hourly
May titrate up to 1 mg 24 hourly at weekly intervals
Target dose: 2 mg PO 24 hourly
Max dose: 2-3 mg PO 24 hourly
Cariprazine  Initial dose: 1.5 mg PO 24 hourly
Dose may be adjusted up to 3 mg PO 24 hourly on day 15 based on response/tolerability
Max dose: 3 mg PO 24 hourly 

Adverse Reactions

  • Hematologic effects (leukopenia, neutropenia); CNS effects (depression, extrapyramidal syndromes, syncope); GI effects (Nausea/vomiting); Other effects (salivary hypersecretion, blurred vision, impair core body temperature regulation)

Special Instructions

  • Use with caution in patients with Parkinson's disease, seizure disorders, DM, known CV disease
  • May impair ability to drive or operate machinery
  • Monitor for suicidal ideation or clinical worsening, BP, CBC, fasting blood glucose/HbA1c, fasting lipid profile should be tested at the start of therapy then monitored periodically
  • Discontinue if with severe neutropenia (absolute neutrophil count <1000 mm3)
  • Avoid abrupt withdrawal

Disclaimer

All dosage recommendations are for non-pregnant and non-breastfeeding women and adults with normal renal and hepatic function unless otherwise stated. 
Not all products are available or approved for above use in all countries. 
Products listed in the Drug Summary are based on indications stated in the locally approved product monographs. 
Please refer to local product monographs in Related MIMS Drugs for country-specific prescribing information. 

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