Interactions Between Nonprescription Products and Psychotropic Medications

W. Steven Pray, PhD, DPh


US Pharmacist. 2007;32(11):12-15. 

In This Article

Omeprazole and Diazepam

Nonprescription omeprazole carries a drug interaction warning against concomitant use with diazepam.[6] Omeprazole can inhibit the metabolism of diazepam, elevating its blood concentrations.

Several nonprescription medications contain nonspecific warnings against use with any prescription product without a pharmacist or physician's advice, which of necessity would include all psychotropic medications. They include naproxen, ibuprofen, and codeine-containing schedule V cough syrups.[6] As an example of the importance of these warnings, naproxen and ibuprofen both increase serum lithium levels when given concurrently with it.[7]

A global precaution also applies to medications that could alter the absorption of others, such as psyllium. One manufacturer warns against taking any other prescription medication two hours before or two hours after ingesting psyllium, as the medication may be trapped in the psyllium matrix and unavailable for absorption.[6]


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.