Answer
Combining lidocaine hydrochloride + phenylephrine hydrochloride topical solution with ergot alkaloids increases the risk of ergotism because of its phenylephrine component.
Sources for this answer
- Lidocaine Hydrochloride 5% w/v and Phenylephrine Hydrochloride 0.5% w/v Topical SolutionMartindale Pharma, an Ethypharm Group Company · emc · SmPC §4.5 Interaction with other medicinal products · Version 2Document updated
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