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Drug Treatment of Bipolar Disorders


William Coryell

, MD, Carver College of Medicine at University of Iowa

Last full review/revision Mar 2020| Content last modified Jun 2021

Drug Selection and Use

Choice of drug can be difficult because all drugs have significant adverse effects, drug interactions are common, and no drug is universally effective. Selection should be based on what has previously been effective and well-tolerated in a given patient. If there is no prior experience (or it is unknown), choice is based on the patient’s medical history (vis-à-vis the adverse effects of the specific mood stabilizer) and the severity of symptoms.

For severe manic psychosis, in which immediate patient safety and management is compromised, urgent behavioral control usually requires a sedating 2nd-generation antipsychotic, sometimes supplemented initially with a benzodiazepine such as lorazepam or clonazepam 2 to 4 mg IM or orally three times a day.

For less severe acute episodes in patients without contraindications (eg, renal disorders), lithium is a good first choice for both mania and depressive episodes. Because its onset is slow (4 to 10 days), patients with significant symptoms may also be given an anticonvulsant or a 2nd-generation antipsychotic.

For patients with depression, lamotrigine may be a good choice of anticonvulsant.

For bipolar depression, the best evidence suggests using quetiapine or lurasidone alone or the combination of fluoxetine and olanzapine.

Once remission is achieved, preventive treatment with mood stabilizers is indicated for all bipolar I patients (bipolar I is defined by the presence of at least one full-fledged manic episode and usually depressive episodes). If episodes recur during maintenance treatment, clinicians should determine whether adherence is poor and, if so, whether nonadherence preceded or followed recurrence. Reasons for nonadherence should be explored to determine whether a change in mood stabilizer type or dosing would render treatment more acceptable.


As many as two thirds of patients with uncomplicated bipolar disorder respond to lithium, which attenuates bipolar mood swings but has no effect on normal mood.

Whether lithium or another mood stabilizer is being used, breakthroughs are more likely in patients who have mixed states, rapid-cycling forms of bipolar disorder (usually defined as ≥ 4 episodes/yr), comorbid anxiety, substance use disorder, or a neurologic disorder.

Lithium carbonate is started at 300 mg orally two or three times a day and titrated, based on steady-state blood levels and tolerance, to a range of 0.8 to 1.2 mEq/L (0.8 to 1.2 mmol/L). Levels should be drawn after 5 days at a stable dose and 12 hours after the last dose. Target drug levels for maintenance are lower, about 0.6 to 0.7 mEq/L (0.6 to 0.7 mmol/L). Higher maintenance levels are more protective against manic (but not depressive) episodes but have more adverse effects. Adolescents, whose glomerular function is excellent, need higher doses; older patients need lower doses.

Lithium can cause sedation and cognitive impairment directly or indirectly (by causing hypothyroidism) and often exacerbates acne and psoriasis. The most common acute, mild adverse effects are fine tremor, fasciculation, nausea, diarrhea, polyuria, polydipsia, and weight gain (partly attributed to drinking high-calorie beverages). These effects are usually transient and often respond to decreasing the dose slightly, dividing the dose (eg, three times a day), or using slow-release forms. Once dosage is established, the entire dose should be given after the evening meal. This dosing may improve adherence. A beta-blocker (eg, atenolol 25 to 50 mg orally once a day) can control severe tremor; however, some beta-blockers (eg, propranolol) may worsen depression.

Acute lithium toxicity is manifested initially by gross tremor, increased deep tendon reflexes, persistent headache, vomiting, and confusion and may progress to stupor, seizures, and arrhythmias. Toxicity is more likely to occur in the following:

  • Older patients
  • Patients with decreased creatinine clearance
  • Those with sodium loss (eg, due to fever, vomiting, diarrhea, or use of diuretics)

Thiazide diuretics, angiotensin-converting enzyme (ACE) inhibitors, and nonsteroidal anti-inflammatory drugs (NSAIDs) other than aspirin may contribute to hyperlithemia. Lithium blood levels should be measured every 6 months and whenever the dose is changed.

Long-term adverse effects of lithium include

  • Hypothyroidism, particularly when there is a family history of hypothyroidism
  • Renal damage involving the distal tubule that appears after ≥ 15 years of lithium treatment

Therefore, thyroid-stimulating hormone (TSH) levels should be monitored when lithium is started and annually thereafter if there is a family history of thyroid dysfunction or every other year for all other patients. Levels should also be measured whenever symptoms suggest thyroid dysfunction (including when mania recurs) because hypothyroidism may blunt the effect of mood stabilizers. Blood urea nitrogen (BUN) and creatinine should be measured at baseline, 2 or 3 times during the first 6 months, and then once or twice a year. Cumulative dose is a risk factor for renal damage so the minimal effective dose for effective prophylaxis should be used (1–3).

Lithium references

  • 1. Presne C, Fakhouri F, Noël LH, et al: Lithium-induced nephropathy: Rate of progression and prognostic factors. Kidney Int 64 (2):585–592, 2003. doi: 10.1046/j.1523-1755.2003.00096.x.
  • 2. Pawar AS, Kattah AG: Lithium-induced nephropathy. N Engl J Med 378 (11):1042, 2018. doi: 10.1056/NEJMicm1709438.
  • 3. McKnight RF, Adida M, Stockton S, et al: Lithium toxicity profile: A systematic review and meta-analysis. Lancet 379 (9817):721-728, 2012. doi: 10.1016/S0140-6736(11)61516-X.


Anticonvulsants that act as mood stabilizers, especially valproate and carbamazepine, are often used for acute mania and for mixed states (mania and depression). Lamotrigine is effective for mood-cycling and for depression. The precise mechanism of action for anticonvulsants in bipolar disorder is unknown but may involve gamma-aminobutyric acid mechanisms and ultimately G-protein signaling systems. Their main advantages over lithium include a wider therapeutic margin and lack of renal toxicity.

For valproate, a loading dose of 20 to 30 mg/kg is given, then 250 to 500 mg orally three times a day (extended-release formulation can be used); target blood levels are between 50 and 125 μg/mL (347 and 867 micromol/L). This approach does not result in more adverse effects than does gradual titration. Adverse effects include nausea, headache, sedation, dizziness, and weight gain; rare serious effects include hepatotoxicity and pancreatitis.

Carbamazepine should not be loaded; it should be started at 200 mg orally twice a day and be increased gradually in 200-mg/day increments to target levels between 4 and 12 μg/mL (17 and 51 micromol/L; maximum, 800 mg twice a day). Adverse effects include nausea, dizziness, sedation, and unsteadiness. Very severe effects include aplastic anemia and agranulocytosis.

Lamotrigine is started at 25 mg orally once a day for 2 weeks, then 50 mg once a day for 2 weeks, then 100 mg a day for 1 week, and then can be increased by 50 mg each week as needed up to 200 mg once a day. Dosage is lower for patients taking valproate and higher for patients taking carbamazepine. Lamotrigine can cause rash and, rarely, the life-threatening Stevens-Johnson syndrome, particularly if the dosage is increased more rapidly than recommended. While taking lamotrigine, patients should be encouraged to report any new rash, hives, fever, swollen glands, sores in the mouth and on the eyes, and swelling of the lips or tongue.


Acute manic psychosis is being increasingly managed with 2nd-generation antipsychotics, such as

  • Risperidone (usually 2 to 3 mg orally twice a day)
  • Olanzapine (usually 5 to 10 mg orally twice a day)
  • Quetiapine (200 to 400 mg orally twice a day)
  • Ziprasidone (40 to 80 mg orally twice a day)
  • Aripiprazole (10 to 30 mg orally once/day)
  • Cariprazine (1.5 to 3.0 mg once/day)
  • Lurasidone (20 to 120 mg once/day)

In addition, evidence suggests that these drugs may enhance the effects of mood stabilizers after the acute phase.

Although any of these drugs may have extrapyramidal adverse effects and cause akathisia, risk is lower with more sedating drugs such as quetiapine and olanzapine. Less immediate adverse effects include substantial weight gain and development of the metabolic syndrome (including weight gain, excess abdominal fat, insulin resistance, and dyslipidemia); risk may be lower with the least sedating 2nd-generation antipsychotics, ziprasidone and aripiprazole.

For extremely hyperactive psychotic patients with poor food and fluid intake, an antipsychotic given IM plus supportive care in addition to lithium or an anticonvulsant may be appropriate.


Specific antidepressants (eg, selective serotonin reuptake inhibitors [SSRIs]) are sometimes added for severe depression, but their effectiveness is controversial; they are generally not recommended as sole therapy for depressive episodes, though there is evidence than an SSRI (specifically sertraline) may be safe and effective as monotherapy for bipolar 2 depression (1).



Starting Dose*

Therapeutic Dosage Range



Cause discontinuation symptoms† if stopped abruptly (less likely with fluoxetine)


20 mg once/day

20–40 mg

Lower potential for drug interactions because it has less effect on CYP450 isoenzymes

Risk of QT-interval prolongation that limits doses to ≤ 40 mg/day


10 mg once/day

10–20 mg

Lower potential for drug interactions because it has less effect on CYP450 isoenzymes


10 mg once/day

20–60 mg

Has very long half-life

Less likely to cause discontinuation symptoms†

The only antidepressant proven effective in children


50 mg once/day

100–200 mg

Can cause clinically significant elevation of theophylline, warfarin, and clozapine blood levels

Has potential for interactions between its active metabolites and HCAs, carbamazepine, antipsychotics, or type 1C antiarrhythmics

Has CYP450 profile similar to fluoxetine


20 mg once/day

25 mg CR once/day

20–50 mg

25–62.5 mg CR

Has potential for interactions between its active metabolites and HCAs, carbamazepine, antipsychotics, or type 1C antiarrhythmics

Has CYP450 profile similar to fluoxetine

Of SSRIs, may cause the most weight gain


50 mg once/day

50–200 mg

Of SSRIs, has highest incidence of loose stools


10 mg orally once/day for 7 days, then increase to 20 mg daily for 7 days

10–40 mg (titrate by 5–10 mg every 7 days)

May increase risk of bleeding if the drug is taken with aspirin, other NSAIDs, or other drugs that affect coagulation

Should not be stopped abruptly; reduce dose gradually

Serotonin modulators (5-HT2 blockers)

Cause discontinuation symptoms† if stopped abruptly


15 mg once/day

15–45 mg

Causes weight gain and sedation

Has fewer sexual adverse effects than SSRIs and serotonin- norepinephrine reuptake inhibitors


50 mg three times a day

150–300 mg

May cause priapism and sedation

May cause orthostatic hypotension

Serotonin- norepinephrine reuptake inhibitors

Cause discontinuation symptoms† if stopped abruptly


50 mg once/day

50–100 mg

May increase BP or HR (control BP before initiating the drug and monitor BP and HR while patients are taking the drug)


20 mg twice a day

60–120 mg

Modest dose-dependent increase in systolic and diastolic BP

May cause mild urinary hesitancy in males

Less potential for drug-drug interactions because it has less effect on CYP450 isoenzymes


20 mg once/day for 2 days, then 40 mg once/day

40–120 mg (increase dose in increments of 40 mg/day at intervals of ≥ 2 days; not to exceed 120 mg/day)

May increase BP or HR (control BP before initiating the drug and monitor BP and HR while patients are taking the drug)

May increase risk of bleeding if the drug is taken with aspirin, other NSAIDs, or anticoagulants

Can affect urinary hesitation or retention (caution required in patients with obstructive urinary disorders; stop the drug if symptoms develop)


25 mg three times/day

37.5 mg XR once/day

75–375 mg

72–225 mg XR

Modest dose-dependent increase in diastolic BP

Dual norepinephrine and 5-HT reuptake effect at about 150 mg

Rarely, increase in systolic BP (not dose-dependent)

If stopped, should be tapered slowly

Less potential for drug-drug interactions because it has less effect on CYP450 isoenzymes


5–10 mg once/day

10–20 mg

May increase risk of bleeding if the drug is taken with aspirin, other NSAIDs, or other drugs that affect coagulation or bleeding

Norepinephrine- dopamine reuptake inhibitor


100 mg twice/day

150 mg SR once/day

150 mg XL once/day

200–450 mg

Contraindicated in patients who have bulimia or who are seizure-prone

May interact with HCAs, increasing the risk of seizures

May cause dose-dependent recent memory loss


Contraindicated in patients with coronary artery disease, certain arrhythmias, angle-closure glaucoma, benign prostatic hypertrophy, or esophageal hiatus hernia

Can cause orthostatic hypotension leading to falls and fractures, potentiate the effect of alcohol, and raise the blood level of antipsychotics

Cause discontinuation symptoms† if stopped abruptly

With significant overdose, potentially lethal


50 mg once/day

150–300 mg

Causes weight gain


50 mg twice/day

150–400 mg

Can have extrapyramidal adverse effects


25 mg once/day

100–250 mg

Lowers seizure threshold at doses of > 250 mg/day


25 mg once/day

150–300 mg


25 mg once/day

150–300 mg

Causes weight gain


25 mg once/day

150–300 mg

May cause excessive sweating and nightmares


75 mg once/day

150–225 mg

Increased risk of seizures with rapid dose escalation at high doses


25 mg once/day

50–150 mg

Effective within the therapeutic window


5 mg three times/day

15–60 mg

Has long half-life (74 hours)


50 mg once/day

150–300 mg

Causes weight gain


Serotonin syndrome possible when taken with an SSRI

Hypertensive crisis possible when taken with other antidepressants, sympathomimetic or other selective drugs, or certain foods and beverages

With significant overdose, potentially lethal


10 mg twice/day

30–60 mg

Causes orthostatic hypotension


15 mg three times/day

45–90 mg

Causes orthostatic hypotension

Selegiline, transdermal

6 mg once/day

12 mg

Can cause application site reactions and insomnia


10 mg twice/day

30–60 mg

Causes orthostatic hypotension

Has amphetamine-type stimulant effects and modest abuse potential

Melatonergic antidepressant

Agomelatine (5-HT2C receptor antagonist)

25 mg once/day at bedtime

25–50 mg

Should be stopped immediately if symptoms or signs of potential liver injury develop or if serum aminotransferases increase to > 3 times the upper limit of normal

* All drugs are given orally except for transdermal selegiline.

† Discontinuation symptoms include nausea, chills, muscle aches, dizziness, anxiety, irritability, insomnia, and fatigue.

BP= blood pressure; CR = continuous release; CYP450 = cytochrome P-450 system; HCAs = heterocyclic antidepressants; HR = heart rate; 5-HT = 5-hydroxytryptamine ( serotonin); MAOIs = monoamine oxidase inhibitors; NSAID = nonsteroidal anti-inflammatory drug; SR = sustained release; SSRI = selective serotonin; XL = extended release; XR = extended release.

Antidepressants reference

  • Gitlin MJ: Antidepressants in bipolar depression: An enduring controversy. Int J Bipolar Disord 6:25, 2018. doi: 10.1186/s40345-018-0133-9.

Precautions During Pregnancy

Lithium use during pregnancy has been associated with an increased risk of cardiovascular malformations (particularly Ebstein anomaly). However, the absolute risk of this particular malformation is quite low. Taking lithium during pregnancy appears to increase the relative risk of any congenital anomaly by about 2-fold, a risk similar to the 2- to 3-fold increased risk of congenital anomalies associated with use of carbamazepine or lamotrigine and is substantially lower than the risk associated with use of valproate.

With valproate, risk of neural tube defects and other congenital malformations appears to be 2 to 7 times higher than that with other commonly used anticonvulsants. Valproate increases the risk of neural tube defects, congenital heart defects, genitourinary anomalies, musculoskeletal abnormalities, and cleft lip or palate. Also, cognitive outcomes (eg, IQ scores) in children of women who took valproate during pregnancy are worse than those with other anticonvulsants; risk appears to be dose-related. Valproate also appears to increase risk of attention-deficit/hyperactivity disorder and autism spectrum disorders (1).

Extensive study of the use of 1st-generation antipsychotics and tricyclic antidepressants during early pregnancy has not revealed causes for concern. The same appears to be true of selective serotonin reuptake inhibitors (SSRIs), except for paroxetine. Data about the risks of 2nd-generation antipsychotics to the fetus are sparse as yet, even though these drugs are being more widely used for all phases of bipolar disorder.

Use of drugs (particularly lithium and SSRIs) before parturition may have postpartum effects on neonates.

Treatment decisions are complicated by the fact that with unplanned pregnancy, teratogenic effects may already have taken place by the time practitioners become aware of the issue. Consultation with a perinatal psychiatrist should be considered. In all cases, discussing the risks and benefits of treatment with patients is important.

Precautions during pregnancy reference

  • 1. Tomson T, Battino D, Perucca E: Valproic acid after five decades of use in epilepsy: Time to reconsider the indications of a time-honoured drug. Lancet Neurol 15 (2): 210–218, 2016. doi: 10.1016/S1474-4422(15)00314-2.

Drugs Mentioned In This Article

Drug Name Select Trade
Tranylcypromine PARNATE
Levomilnacipran FETZIMA
Desvenlafaxine PRISTIQ
Amitriptyline No US brand name
Protriptyline VIVACTIL
Isocarboxazid MARPLAN
carbamazepine TEGRETOL
Nortriptyline AVENTYL
Clomipramine ANAFRANIL
Vortioxetine Vortioxetine
theophylline ELIXOPHYLLIN
Aripiprazole ABILIFY
Escitalopram LEXAPRO
Trimipramine Trimipramine
Ziprasidone GEODON
Desipramine NORPRAMIN
propranolol INDERAL
Fluvoxamine LUVOX
Venlafaxine EFFEXOR XR
Risperidone RISPERDAL
Cariprazine VRAYLAR
lamotrigine LAMICTAL
Mirtazapine REMERON
amphetamine ADDERALL XR 10
Paroxetine PAXIL
sertraline ZOLOFT
Selegiline ELDEPRYL
Vilazodone Vilazodone
Phenelzine NARDIL
Citalopram CELEXA
lurasidone LATUDA
fluoxetine PROZAC, SARAFEM
Imipramine TOFRANIL
olanzapine ZYPREXA
clonazepam KLONOPIN
Duloxetine CYMBALTA
quetiapine SEROQUEL
Trazodone OLEPTRO
lorazepam ATIVAN
clozapine CLOZARIL
warfarin COUMADIN
atenolol TENORMIN
lithium LITHOBID

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