A nurse is reviewing the medication administration record of a client who has benign prostatic hyperplasia (BPH). The client asks the nurse about taking saw palmetto. The nurse should instruct the client that which of the following medications interacts adversely with saw palmetto?

Rationale: A. Penicillin: Saw palmetto does not interfere with antibiotic action or metabolism. No significant pharmacodynamic or pharmacokinetic interaction exists between penicillin and saw palmetto. B. Zolpidem: While both may cause some central nervous system effects, there is no established adverse interaction between zolpidem and saw palmetto. Co-administration is generally not contraindicated. C. Clopidogrel: Saw palmetto has antiplatelet properties and can potentiate the effects of clopidogrel, increasing the risk of bleeding. Clients taking both may face elevated risk of gastrointestinal or intracranial hemorrhage. D. Ipratropium: Ipratropium is an anticholinergic agent used primarily for respiratory conditions. It does not have a known interaction with saw palmetto, and their pharmacologic mechanisms do not overlap.