Bipolar disorder is characterized by episodes of mania, hypomania, and depression. Recurrences of manic or (more frequently) depressive symptoms are common. About 15-20% of patients with bipolar disorder die by suicide.

Bipolar disorder is characterized by episodes of mania, hypomania, and depression. Recurrences of manic or (more frequently) depressive symptoms are common. About 15-20% of patients with bipolar disorder die by suicide.

Three extended-release injectable formulations of second-generation antipsychotic drugs — two of risperidone (Rykindo, Uzedy) and one of aripiprazole (Abilify Asimtufii) — have been approved by the FDA for treatment of schizophrenia in adults. Rykindo and Abilify Asimtufii are also approved for maintenance treatment of bipolar I disorder in adults. Other extended-release injectable formulations of risperidone and aripiprazole have been available in the US for years (see Table 1).

The FDA has approved a sublingual film formulation of the alpha-2 adrenergic receptor agonist dexmedetomidine (Igalmi — BioXcel Therapeutics) for acute treatment of agitation associated with schizophrenia or bipolar I or II disorder in adults. It is the first alpha-2 agonist and the only sublingual film to be approved for this indication. Dexmedetomidine has been available for many years in an injectable formulation (Precedex) for sedation in the intensive care unit and to facilitate procedures such as mechanical ventilation.

Invega Hafyera (Janssen), a long-acting, extended-release (ER) formulation of the second-generation antipsychotic paliperidone palmitate, has been approved by the FDA for twice-yearly IM treatment of schizophrenia in adults who have been adequately treated with another injectable ER formulation of the drug (Invega Sustenna or Invega Trinza). It is the first drug to become available in the US for twice-yearly treatment of schizophrenia.

The FDA has approved lumateperone (Caplyta — Intracellular Therapies), an oral second-generation antipsychotic, for once-daily treatment of schizophrenia in adults. It is the 13th second-generation antipsychotic drug to be approved by the FDA for this indication.

Alzheimer's disease (AD) is the most common cause of dementia, but cognitive loss is also associated with other neurological conditions such as Parkinson's disease, dementia with Lewy bodies, vascular dementia, and frontotemporal dementia.

Oral antipsychotic drugs used for treatment of schizophrenia, schizoaffective disorder, delusional disorder, and other manifestations of psychosis or mania are listed in Table 1. Parenteral antipsychotic drugs used for treatment of these disorders are listed in Table 2.

Bipolar disorder is characterized by intermittent episodes of mania and/or depression. Even with maintenance treatment, recurrences of manic or (more frequently) depressive episodes are common. Some of the drugs and dosages recommended here have not been approved by the FDA for use in bipolar disorder.

The FDA has approved cariprazine (Vraylar – Actavis), an oral, once-daily, second-generation antipsychotic, for treatment of schizophrenia and for acute treatment of manic or mixed episodes associated with bipolar I disorder.

The FDA has approved two new long-acting injectable formulations of second-generation antipsychotics for treatment of schizophrenia: aripiprazole lauroxil (Aristada – Alkermes), which is given once every 4-6 weeks, and paliperidone palmitate (Invega Trinza – Janssen), which is given once every 3 months. Once-monthly injectable formulations of aripiprazole (Abilify Maintena) and paliperidone palmitate (Invega Sustenna) were approved earlier.

The FDA has approved the oral, once-daily, second-generation antipsychotic brexpiprazole (Rexulti – Otsuka/Lundbeck) for treatment of schizophrenia and as an adjunct to antidepressants for treatment of major depressive disorder (MDD). Aripiprazole (Abilify), a structurally similar second-generation antipsychotic also comarketed by Otsuka (with BMS), recently became available generically.

Alzheimer's disease (AD) is the most common cause of dementia, but cognitive loss is also associated with other neurological conditions such as Parkinson's disease, dementia with Lewy bodies, and vascular dementia. Mild cognitive impairment (MCI) is generally defined as cognitive decline greater than expected for an individual's age and educational level, but not interfering with activities of daily living; it may be a transitional state between the cognitive changes of normal aging and dementia.

Drugs are not the only treatment for psychiatric illness. Psychotherapy remains an important component in the management of these disorders, and cognitive behavioral therapy (CBT) can be used for many of them as well. Electroconvulsive therapy (ECT) has a long history of efficacy and safety when drugs are ineffective or cannot be used.

An extended-release injectable formulation of the second-generation antipsychotic aripiprazole (Abilify) has been approved by the FDA (Abilify Maintena – Otsuka/Lundbeck) for once-monthly treatment of schizophrenia. It is the fourth second-generation antipsychotic to become available in a long-acting parenteral formulation. Long-acting parenteral antipsychotics, given at intervals of 2-4 weeks, are generally used for patients with a history of relapse due to poor adherence to oral maintenance therapy.

Augmentation with a second-generation (atypical) antipsychotic is a treatment option for patients with major depressive disorder (MDD) whose symptoms persist following antidepressant monotherapy. Aripiprazole (Abilify), olanzapine in a fixed-dose combination with fluoxetine (Symbyax), and extended-release quetiapine (Seroquel XR) have been approved by the FDA for such use.

The FDA has approved lurasidone (Latuda - Sunovion), a new second-generation antipsychotic, for oral treatment of schizophrenia in adults.

The antipsychotic drugs listed in Table 1 on the next page are more effective for treating the “positive symptoms” of schizophrenia (hallucinations and delusions) than the “negative symptoms” (apathy, social withdrawal, and blunted affect). Some symptoms of schizophrenia and acute psychoses may improve rapidly after treatment with antipsychotic drugs, but chronic schizophrenia improves slowly over many weeks and some patients may continue to improve for months. Most patients with chronic schizophrenia require prolonged maintenance therapy, but the risk of tardive dyskinesia and adverse metabolic effects must be kept in mind.

Drugs are not the only treatment for mood disorders. Psychotherapy remains an important component in the management of these disorders, and electroconvulsive therapy (ECT) has a long history of efficacy and safety when drugs are ineffective, poorly tolerated or cannot be used. Some drugs are recommended here for indications that have not been approved by the FDA.

The FDA has approved the marketing of iloperidone (Fanapt – Vanda), a second-generation antipsychotic, for treatment of schizophrenia. Iloperidone is chemically related to risperidone (Risperdal, and others).

Asenapine (Saphris - Schering-Plough), a dibenzo-oxepino pyrrole, has been approved by the FDA in a sublingual tablet formulation for acute treatment of schizophrenia and manic or mixed episodes associated with bipolar disorder. It is the sixth second-generation antipsychotic approved by the FDA for use in bipolar disorder.

Paliperidone palmitate (Invega Sustenna – Ortho-McNeil Janssen) has been approved by the FDA as a once-monthly injection for acute and maintenance treatment of schizophrenia in adults. An extended-release oral formulation (Invega) has been available since 2006.1 Long-acting injections of antipsychotic drugs typically are used to treat patients who cannot adhere to an oral regimen.2,3 Paliperidone is the primary active metabolite of risperidone (Risperdal), which is also available as a long-acting (every 2 weeks) injection. It is unclear whether either risperidone or paliperidone is a better choice for long-term treatment of schizophrenia than a first-generation drug such as haloperidol, which can also be injected once a month and costs much less.4

1. Paliperidone (Invega) for schizophrenia. Med Lett Drugs Ther 2007; 49:21.
2. JC West et al. Use of depot antipsychotic medications for medication non-adherence in schizophrenia. Schizophr Bull 2008; 34:995.
3. D Hough et al. Safety and tolerability of deltoid and gluteal injections of paliperidone palmitate in schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry 2009; 33:1022.
4. Drugs for psychiatric disorders. Treat Guidel Med Lett 2006; 4:35.

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Readers have asked us to update our 2004 article on tablet splitting. Breaking drug tablets in half is a common practice, but the FDA recently advised consumers against it (FDA Consumer Health Information, July 2009).

Tetrabenazine (Xenazine - Ovation Pharmaceuticals), an old drug first synthesized 50 years ago for treatment of schizophrenia, was recently approved by the FDA for the treatment of chorea associated with Huntington's disease. It has been available in other countries for decades.

Paliperidone (Invega - Janssen) has been approved by the FDA in an extended-release formulation for treatment of schizophrenia. It is the primary active metabolite of the second-generation antipsychotic risperidone (Risperdal - Janssen), which is scheduled to lose its patent exclusivity in December 2007.

Drugs are not the only treatment for psychiatric illness. Psychotherapy remains an important component in the management of these disorders, and cognitive behavioral therapy (CBT) is used for many of them as well. Electroconvulsive therapy (ECT) has a long history of efficacy and safety when drugs are ineffective or cannot be used.

Aripiprazole (Abilify - Bristol-Myers Squibb/Otsuka), a second-generation (atypical) antipsychotic drug, was approved by the FDA in 2002 for treatment of schizophrenia and more recently for bipolar disorder as well. It has been promoted as causing fewer adverse effects than other antipsychotics, without sacrificing efficacy.

The FDA recently cleared the AmpliChip CYP450 Test (Roche), which analyzes blood-derived DNA to detect genetic variations in the activity of cytochrome P450 (CYP) enzymes CYP2D6 and CYP2C19 and determines the metabolizer status of the patient. The test is intended to help guide clinicians in prescribing individualized drug therapy. About 25% of all drugs, including many antidepressants and antipsychotics, are substrates of either CYP2D6 or CYP2C19. The test is being promoted initially to psychiatrists.

The FDA has reported that 5106 elderly patients with dementia treated with atypical (second generation) antipsychotics in 17 randomized controlled trials had a higher mortality rate (4.5% vs. 2.6%) than those receiving placebo. Most of the deaths were due to cardiovascular and infectious causes (such as pneumonia). The drugs used in the trials were aripiprazole (Abilify), olanzapine (Zyprexa), quetiapine (Seroquel), and risperidone (Risperdal). As the increase in mortality was considered a class effect, the FDA advisory also included ziprasidone (Geodon), clozapine (Clozaril) and the olanzapine/fluoxetine combination (Symbyax). The manufacturers of all of these drugs will be required to add a "black box" warning to their labeling.

An extended-release formulation of carbamazepine, available since 1997 for treatment of epilepsy, has now been approved under a new name, Equetro, for acute mania and mixed episodes of bipolar disorder. Although the drug was effective in some patients for up to 6 months, it has not been approved for maintenance treatment. Carbamazepine has not been shown to be more effective than lithium or valproate, and it can cause serious adverse effects.

A recent supplement to the Journal of Clinical Psychiatry, titled "The Expert Consensus Guideline Series: Optimizing Pharmacologic Treatment of Psychotic Disorders," concluded that most experts endorsed use of second-generation (atypical) antipsychotics rather than first-generation drugs, with risperidone (Risperdal - Janssen) the top choice for first episodes, multiple episodes or switches from another drug (JM Kane et al, J Clin Psychiatry 2003; 64 suppl 12:5). The supplement was sponsored by Janssen.

The number of drugs marketed for psychiatric indications has increased sharply in recent years. The recommendations in this article are based on the results of controlled trials and on the experience and opinions of Medical Letter consultants. Interactions with other drugs can be found in The Medical Letter Handbook of Adverse Drug Interactions, 2003.

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

Aripiprazole (Abilify - Bristol-Myers Squibb/Otsuka), a quinolinone derivative, has been approved by the FDA for treatment of schizophrenia.

Ziprasidone (Geodon - Pfizer), a benzisothiazolyl piperazine, has been approved by the FDA for oral treatment of schizophrenia. An intramuscular formulation will probably be available in the near future.

Quetiapine (Seroquel - Zeneca), a dibenzothiazepine derivative, has been approved by the FDA for treatment of schizophrenia and other psychotic disorders. It is a new addition to the 'atypical' antipsychotics, which include olanzapine (Zyprexa - Medical Letter, 39:5, 1997), risperidone (Risperdal) and clozapine (Clozaril). Atypical antipsychotic drugs generally are less likely to cause extrapyramidal symptoms than older drugs such as haloperidol (Haldol, and others) or the phenothiazines.

Olanzapine (Zyprexa - Lilly), a thienobenzodiazepine that structurally resembles and binds to many of the same receptors as clozapine (Clozaril), is now available in the USA for treatment of schizophrenia and other psychotic disorders.