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Search the Interaction Finder 

The Interaction Finder allows you to easily search for drug interactions by active substance name or keywords. 


Paxlovid contains nirmatrelvir and ritonavir. Ritonavir is administered with nirmatrelvir as a pharmacokinetic enhancer to increase systemic concentrations1

Ritonavir is a widely used treatment with a known profile2,3
  • Ritonavir is used in combination with other antivirals to similarly inhibit drug metabolism2,3
For a list of potential clinically significant drug interactions, including contraindicated drugs, refer to Section 4.3: Contraindications, Section 4.5: Interaction with other medicinal products and other forms of interaction and Table 1: Interaction with other medicinal products and other forms of interaction of the SmPC [here].1
EXPLORE MOREEfficacy & trial design

Discover the efficacy data and trial design of EPIC-HR. 

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1. PAXLOVID Summary of Product Characteristics. (Accessed October  2023).
2. Owen DR, Allerton CMN, Anderson AS, et al. An oral SARS-CoV-2 Mpro inhibitor clinical candidate for the treatment of COVID-19. Science. 2021;374(6575):1586-1593.
3. NORVIR Summary of Product Characteristics. (Accessed October 2023).
▼ This medicinal product is subject to additional monitoring. This will allow quick identification of new safety information. Healthcare professionals are asked to report any suspected adverse reactions. See section 4.8 of the SmPC for how to report adverse reactions.

Legal Category: S1A
Further information is available upon request

PP-PAX-IRL-0173. October 2023

Adverse events should be reported. Report an adverse event to your national reporting system (HPRA Pharmacovigilance)

Adverse events should also be reported to Pfizer Medical Information on 1800 633 363

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