Discontinuation of Procyclidine Injection and Management of Acute Dystonia

Acute Dystonia: Overview and Clinical Impact

Procyclidine injection, previously used for the treatment of acute dystonia, drug-induced extrapyramidal symptoms, and parkinsonism, has now been discontinued with no further UK supplies available. Acute dystonia is a sudden movement disorder caused by dopamine-blocking medicines such as Haloperidol, resulting in painful muscle spasms, abnormal postures, oculogyric crisis, and in severe cases, airway compromise. In mental health settings where dystonic reactions may follow the administration of IM antipsychotic medication;  we may see this reaction more often. It can be distressing, painful, and potentially life-threatening, which could be devastating to the patient and to the relationship with the clinical staff, hence quick, effective treatment should be administered.

Injectable Alternative: Benztropine Mesylate

Where urgent treatment is needed and the patient is unable to take oral medication, the current preferred alternative is benztropine mesylate injection, given at a dose of 1–2 mg IM or IV, followed by oral anticholinergic treatment if required. However, benztropine is only available in the UK as an unlicensed import, requiring patient-named ordering, with longer lead times.

Oral Treatment Option: Procyclidine Tablets

Where the patient can swallow, oral procyclidine remains the most practical option and should be used whenever clinically appropriate. Mental health services should review local protocols to ensure that effective alternatives are available, especially where IM antipsychotics are used, as untreated acute dystonia can rapidly escalate and cause severe distress. Advance planning for access to injectable alternatives and staff awareness of early symptoms are essential to ensure prompt treatment, and to maintain safe patient care.