Phenergan (promethazine) interacts with numerous medications. Concurrent use with CNS depressants, such as opioids (morphine, codeine), benzodiazepines (diazepam, alprazolam), and alcohol, significantly increases the risk of respiratory depression and sedation. Monitor patients closely for these effects, and consider dose reduction.
MAO inhibitors interact dangerously with Phenergan, potentially causing severe hypertension. Avoid concomitant use. A minimum two-week gap should separate discontinuation of MAOIs and Phenergan administration.
Phenergan can potentiate the effects of anticholinergics (e. g., atropine, antihistamines), leading to increased dry mouth, constipation, and urinary retention. Observe patients for these side effects.
The anticoagulant effect of warfarin can be increased by Phenergan, raising the bleeding risk. Regular monitoring of INR is crucial.
Combining Phenergan with other medications that cause orthostatic hypotension increases the likelihood of falls. Patients should be advised to rise slowly from a lying or sitting position.
This information is not exhaustive; consult a comprehensive drug reference for a complete list of interactions. Always check for potential drug interactions before administering Phenergan.
