A client taking MAOI phenelzine (Nardil) tells nurse that he routinely takes all of medications listed below. Which medication would cause nurse to express concern and refore initiate furr teaching?

Correct Answer: B. Diphenhydramine (Benadryl)

Over-the-counter medications used for allergies and cold symptoms are contraindicated because they will increase the sympathomimetic effects of MAOIs, possibly causing a hypertensive crisis. In general, SSRIs, SNRIs, TCAs, bupropion, mirtazapine, St. John’s Wort and sympathomimetic amines, including stimulants, are contraindicated with MAOIs. Tramadol, meperidine, dextromethorphan, and methadone are contraindicated in patients on MAOIs as they are at high risk for causing serotonin syndrome.

• Option A: Acetaminophen (APAP) is considered a non-opioid analgesic and antipyretic agent used to treat pain and fever. Clinicians can use it for their patients as a single agent for mild to moderate pain and in combination with an opioid analgesic for severe pain. Acetaminophen, also called N-acetyl para-aminophenol or paracetamol, is one of the most widely used over-the-counter analgesic and antipyretic agents. Although its exact mechanism of action remains unclear, it is historically categorized along with NSAIDs because it inhibits the cyclooxygenase (COX) pathways.
• Option C: The Food and Drug Administration (FDA) has approved the use of furosemide in the treatment of conditions with volume overload and edema secondary to congestive heart failure exacerbation, liver failure, or renal failure including the nephrotic syndrome. Furosemide inhibits tubular reabsorption of sodium and chloride in the proximal and distal tubules, as well as in the thick ascending loop of Henle by inhibiting sodium-chloride cotransport system resulting in excessive excretion of water along with sodium, chloride, magnesium, and calcium.
• Option D: Isosorbide is a nitrate that exerts its pharmacologic effect by releasing nitric oxide (NO), an endothelium-derived relaxing factor (EDRF).NO is endogenously produced in the endothelium to dilate the blood vessels. It is for the prevention or treatment of angina pectoris resulting from coronary artery disease; however, it is not recommended for use once the anginal episode has started because the onset of action is not sufficiently rapid enough to abort an acute anginal event. In the latter case, glyceryl trinitrate is preferable.