Managing Side Effects of Antipsychotic Agents

Extrapyramidal symptoms are the major side effect of typical antipsychotic medications. The symptoms are very distressing and uncomfortable. Their presence will affect patient's adherence with antipsychotic medications. Prevention and treatment of EPS is essential to keep patients on their medications. In addition, the side effects of the medications should be monitored, for example anticholinergic side effects from benztropine (Cogentin).

Parkinsonism and dystonia (see Table 21-7 Signs of Extrapyramidal Side Effects for description of symptoms) can be treated by antiparkinsonian drugs such as benztropine (Cogentin) or trihexyphenidyl (Artane), which are acetylcholine (muscarinic) receptor antagonists (anticholinergics). Akathisia can be resolved with beta blockers such as propranolol (Inderal) and metoprolol (Lopressor). Antihistamines and benzodiazepines are also used. No medication is available to treat tardive dyskinesia. High doses of vitamin E (1600–2000 IU) have been tried. See Table 21-10 Medications for Extrapyramidal Symptoms (EPS) for a list of the medications that treat these symptoms.

Other Side Effects from Antipsychotic Medications

Neuroleptic Malignant Syndrome

Neuroleptic malignant syndrome (NMS) can develop over a few days. This syndrome is uncommon yet potentially fatal. The signs include elevated temperature (>39°C [102°F]), severe EPS, autonomic instability, delirium, and elevation of CPK, WBCs, and liver enzymes. Medical interventions are required. Cooling measures and hydration are needed.

Autonomic Dysfunction

• Tachycardia:Beta blockers may be used if pulse exceeds 100 beats per minute (bpm).
• Sialorrhea (excessive salivation): Can be excessive with clozapine (Clozaril). No anticholinergic agents are recommended to control excessive salivation.
• Dry mouth: Extra care of the mouth and teeth is required because of higher risk of developing cavities.
• Orthostatic hypotension: Patients should be cautioned about the possibility of falling on abrupt change of posture.
• Low-grade fever: The homeostasis for body temperature may be affected by clozapine (Clozaril)

Other Categories of Side Effects

• Elevated cholesterol and triglycerides:Tends to occur in patients on any antipsychotic agents. Type II diabetes may develop in association with the use of antipsychotics.
• Weight gain:Many psychiatric medications are associated with the risk of weight gain.
• Sedation: Common with most psychiatric medications. This can be used for sleep problems.
• Endocrine dysfunction: Most antipsychotic agents (except clozapine and quetiapine) can elevate prolactin levels. This may lead to amenorrhea.
• Liver enzyme elevation: This elevation may be asymptomatic.
• Hematologic dysfunction: All antipsychotic agents can affect CBC values.