Which of the following is a side effect of traditional antipsychotics?

Traditional antipsychotics, also referred to as first-generation antipsychotics, are known to have a range of side effects primarily due to their dopamine receptor antagonism. One notable side effect associated with these medications is Parkinsonism, which includes symptoms such as tremors, rigidity, and bradykinesia. This occurs because these medications block dopamine receptors not only in pathways linked to psychosis but also in areas of the brain that regulate motor control, mimicking the effects of Parkinson's disease.

Understanding the mechanism is essential; by inhibiting dopamine activity in the nigrostriatal pathway, these antipsychotics lead to motor symptoms characteristic of Parkinsonism. This risk increases with the duration and dosage of treatment, making monitoring for such side effects critical when prescribing traditional antipsychotics.

The other options listed do not accurately represent common side effects of traditional antipsychotics. Hyperglycemia can occur with atypical antipsychotics and is not a prominent feature of traditional ones. Weight loss is generally not associated with these medications, as they can often lead to weight gain instead. Acne is not a recognized side effect directly related to the use of antipsychotics.