When recommending OTC medications, it is important to suggest therapies based on patient symptoms, drug interactions and adverse effect profile. Below a summary of safe drugs to use in this population according to symptoms:
Relief of non-productive cough:
Dextromethorphan is a cough suppressant with no reported drug-interactions with immunosuppressant medications. Caution should be exercised in liver transplant patients as dextromethorphan is metabolized by the CYP450 2D6 isoenzyme.
Codeine is typically used as an opioid analgesic but is also used as a cough suppressant in combination products. In patients with low GFR, doses should be reduced (25% - 50% reduction) due to potential for accumulation of metabolites.
Relief of congestion and productive cough:
Guaifenesin is an expectorant with no significant drug-drug interactions, although caution is recommended in renal transplant recipients and in patients with decreased renal function as it is hydrolyzed to a renally eliminated metabolite and high doses of guaifenesin have been rarely associated with urolithiasis.
Antihistamines including diphenhydramine (1st generation) and loratidine (2nd generation) are used for relief of symptoms such as cough, watery eyes, runny nose and sneezing.
Caution should be advised in the following settings: patients on calcineurin inhibitors as antihistamines decrease gastric motility; patients with renal dysfunction due to urinary excretion of antihistamine metabolites (extend dosing interval); liver transplant patients due to hepatic metabolism; and lung transplant patients as antihistamines thicken bronchial secretions and can cause respiratory depression.
Relief of pain
Acetaminophen is an antipyretic/analgesic, which can be used to relieve fever and pains associated with colds. It is considered generally safe to use in renal transplant patients but caution should be used in patients with liver dysfunction.
Don't forget about nonpharmacological therapies, which can be safely utilized to provide relief for cold symptoms: saline sprays, vaporizers and humidifiers.
The following medications are NOT recommended: Pseudoephedrine, Phenylephrine, Oxymetazoline and NSAIDS (Advil, Aleve, Ibuprofen, Motrin, Excedrin, Midol). Patients should be informed to carefully read product ingredients as combination therapies could contain these agents.
Elsen C. Jacob PharmD, Pharmacy Resident
Steven Gabardi PharmD, BCPS, Organ Transplant Clinical Specialist at BWH