Psychopharmacology

PSYCHOPHARMACOLOGY

Medication management is a crucial issue that greatly influences the outcomes of treatment for many clients with mental disorders. The following sections discuss sev-eral categories of drugs used to treat mental disorders (psychotropic drugs): antipsychotics, antidepressants, mood stabilizers, anxiolytics, and stimulants. Nurses should understand how these drugs work; their side effects, contraindications, and interactions; and the nurs-ing interventions required to help clients manage medica-tion regimens.

Several terms used in discussions of drugs and drug therapy are important for nurses to know. Efficacy refers to the maximal therapeutic effect that a drug can achieve. Potency de scribes the amount of the drug needed to achieve that maximum effect; low-potency drugs require higher dosages to achieve efficacy, whereas high-potency drugs achieve efficacy at lower dosages. Half-life is the time it takes for half of the drug to be removed from the bloodstream. Drugs with a shorter half-life may need to be given three or four times a day, but drugs with a longer half-life may be given once a day. The time that a drug needs to leave the body completely after it has been dis-continued is about five times its half-life.

The U.S. Food and Drug Administration (FDA) is responsible for supervising the testing and marketing ofmedications for public safety. These activities include clini-cal drug trials for new drugs and monitoring the effective-ness and side effects of medications. The FDA approves each drug for use in a particular population and for specific diseases. At times, a drug will prove effective for a disease that differs from the one involved in original testing and FDA approval. This is called off-label use. An example is some anticonvulsant drugs (approved to prevent seizures) that are prescribed for their effects in stabilizing the moods of clients with bipolar disorder (off-label use). The FDA also monitors the occurrence and severity of drug side effects. When a drug is found to have serious or life-threatening side effects, even if such side effects are rare, the FDA may issue a black box warning. This means that package inserts must have a highlighted box, separate from the text, which contains a warning about the serious or life-threatening side effects.