Trihexyphenidyl and Ziprasidone interaction
Trihexyphenidyl and Ziprasidone: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Trihexyphenidyl (Trihexyphenidyl Hydrochloride) label · effective 2025-07-02
Neuroleptic Malignant Syndrome A potentially fatal symptom complex sometimes referred to as Neuroleptic Malignant Syndrome (NMS) has been reported in association with dose reduction or Discontinuation of trihexyphenidyl.
Prophylactic administration of anticholinergic agents, such as trihexyphenidyl, as a prevention of drug-induced parkinsonism during neuroleptic therapy is not recommended.
Concurrent use of alcohol or other CNS depressants with trihexyphenidyl HCl may cause increased sedative effects.
There may be an increased risk for the development of tardive dyskinesia during concomitant administration of anticholinergics and neuroleptics ( see PRECAUTIONS , General ).
From the Ziprasidone (Geodon) label · effective 2025-01-13
Other important considerations in the differential diagnosis include central anticholinergic toxicity, heat stroke, drug fever, and primary central nervous system (CNS) pathology.
Appropriate care is advised when prescribing ziprasidone for patients who will be experiencing conditions which may contribute to an elevation in core body temperature, e.g., exercising strenuously, exposure to extreme heat, receiving concomitant medication with anticholinergic activity, or being subject to dehydration.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.