Possible medication error risks with nirmatrelvir+ritonavir

The US Institute for Safe Medication Practices (ISMP) has identified possible medication error risks with nirmatrelvir+ritonavir (Paxlovid), which recently received Emergency Use Authorization (EUA) for the treatment of mild-to-moderate COVID-19 infections in USA. A special alert has been issued to raise awareness of the medication error risks and recommend ways to prevent dosage errors.

Paxlovid is indicated for the treatment of patients with positive COVID-19 test who are at high risk for progression to severe COVID-19 infection. However, dose reduction is necessary for patients with moderate renal impairment, and Paxlovid should not be administered in patients with severe renal impairment.

Paxlovid is only available in a carton of five blister cards, each with morning and evening doses comprised of two tablets of nirmatrelvir and one tablet of ritonavir. The ISMP is advising pharmacists that when Paxlovid is prescribed for patients with moderate renal impairment, one of the nirmatrelvir tablets in each morning and evening dose should be removed from each blister card before being dispensed, and the empty blisters should be covered with manufacturer-supplied stickers.

"Other possible safety issues include challenges with prescribing the dose, patients accidentally failing to take both tablets together, and drug interactions," says the ISMP.

All medication errors should be reported to ISMP's medication error reporting program, as well as to the FDA MedWatch reporting program.