Which is an example of an extrapyramidal side effect?

Extrapyramidal side effects are a group of symptoms that can occur as a result of certain antipsychotic medications, particularly those that block dopamine receptors in the brain. These symptoms can affect movement and coordination, leading to conditions resembling Parkinson's disease. Tremors are a classic example of an extrapyramidal side effect because they involve involuntary muscle contractions and can result in shaking movements that are often seen in individuals with neurological disorders. This side effect is commonly associated with medications that alter the balance of neurotransmitters in the brain, particularly dopamine.

In contrast, weight gain, insomnia, and dizziness are not classified as extrapyramidal side effects. Weight gain can stem from various factors, including metabolic changes from antipsychotic medications but does not directly relate to motor control. Insomnia is primarily a sleep disorder and does not pertain to motor function. Dizziness may arise from various causes, including medication side effects, but is not specifically indicative of extrapyramidal symptoms. Thus, tremors are the most accurate representation of an extrapyramidal side effect among the given options.