Biperiden hydrochloride tablets, as a central anticholinergic agent, may produce adverse reactions in multiple systems while exerting therapeutic effects.

Serious side effects

Neuroleptic malignant syndrome

1. Biperiden hydrochloride tablets may induce neuroleptic malignant syndrome when used in combination with antipsychotics, antidepressants, or dopaminergic antiparkinsonian drugs, particularly upon dose reduction or withdrawal.

2. Clinical features include fever, akinesia with mutism, disturbance of consciousness, marked muscle rigidity, involuntary movements, dysphagia, tachycardia, blood pressure fluctuations, and profuse sweating.

3. Once it occurs, immediate systemic supportive care (e.g., physical cooling, fluid replacement) should be initiated, and the original dosage should be reinstated, followed by a slow taper under close monitoring. This syndrome is often accompanied by elevated leukocyte count and a marked increase in serum creatine kinase (CK); in severe cases, myoglobinuria-induced renal impairment may develop and requires aggressive management.

Dependence formation

Literature reports indicate that biperiden hydrochloride tablets may cause euphoria, and long-term use carries a risk of psychological dependence; during treatment, patients' psychiatric and behavioral changes should be carefully assessed to avoid misuse or off-label use.

Other side effects

Biperiden hydrochloride tablets may also cause the following adverse reactions:

Psychiatric and nervous system: hallucinations, delirium, confusion, anxiety, somnolence, memory impairment.

Digestive system: dry mouth, nausea, vomiting, anorexia, gastric discomfort, diarrhea, constipation, stomatitis.

Urinary system: dysuria, urinary retention.

Allergic reactions: rash.

Cardiovascular system: decreased blood pressure or increased blood pressure.

Ocular: accommodation disorder (e.g., blurred vision).

Liver: hepatic dysfunction; regular monitoring of liver function parameters is recommended during treatment.

In clinical practice, an individualized monitoring plan should be established; particular attention to psychiatric symptoms and cognitive changes is required at treatment initiation and during dose adjustment; in elderly patients, assessment of urination, defecation, and degree of dry mouth should be reinforced; liver function and cardiovascular parameters should be periodically re-evaluated.