nirmatrelvir/ritonavir vs tadalafil
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Side-by-side comparison of nirmatrelvir/ritonavir and tadalafil. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
moderate Known Drug Interaction
Pulmonary hypertension agents (PDE5 inhibitors) tadalafil (Adcirca ® ) ↑ tadalafil Avoid concomitant use of tadalafil with PAXLOVID for pulmonary hypertension. sildenafil, tadalafil, vardenafil ↑ sildenafil ↑ tadalafil ↑ vardenafil Dosage adjustment is recommended for use of sildenafil, tadalafil or vardenafil with PAXLOVID when used for erectile dysfunction.
Paxlovid
Cialis
Paxlovid is a medicine used to treat mild to moderate COVID-19 in adults. It helps prevent severe illness, hospitalization, or death in people at high risk.
Tadalafil (Cialis) is a medicine that helps men with erectile dysfunction (ED) or enlarged prostate (BPH). It belongs to a class of drugs called PDE5 inhibitors.
Paxlovid treats mild to moderate COVID-19 in adults. You must be at high risk of your illness becoming severe. This includes needing to go to the hospital or possibly dying from COVID-19. Paxlovid is not for preventing COVID-19 before or after exposure.
This medicine can help men who have trouble getting or keeping an erection (ED). It can also treat the symptoms of an enlarged prostate, also known as benign prostatic hyperplasia (BPH). BPH can cause difficulty with urination.
Paxlovid contains two medicines, nirmatrelvir and ritonavir. Nirmatrelvir stops the virus from multiplying in your body. Ritonavir helps nirmatrelvir stay in your body longer so it can work better.
Tadalafil works by relaxing the muscles in the penis and prostate. This increases blood flow to these areas. For BPH, it relaxes muscles in the prostate and bladder, which can improve urinary symptoms.
- • Change in taste
- • Diarrhea
- • Headache
- • Upset stomach
- • Back pain
- • Muscle aches
- • Nasal congestion
- COVID-19 22,774
- COVID-19 coming back 20,089
- Change in taste 7,316
- Diarrhea 4,003
- Feeling sick to your stomach 2,620
- Dyspnoea 11,663
- Headache 10,690
- Diarrhoea 7,799
- Nausea 6,498
- Death 5,899
Paxlovid can interact with many other medicines, causing serious or life-threatening problems. Before taking Paxlovid, tell your doctor about all the medicines you take. Your doctor may need to adjust the dose of your other medicines or monitor you more closely.
If you have chest pain, tell your doctor. If you need nitrates for a heart problem, wait 48 hours after taking tadalafil before taking nitrates. If you get an erection that lasts more than 4 hours, get medical help right away. If you have sudden vision loss in one or both eyes, stop taking this medicine and get medical help right away. If you have a sudden decrease or loss of hearing, stop taking this medicine and get medical help right away.
There is not enough information about nirmatrelvir's safety during pregnancy. Studies on ritonavir in pregnant women have not shown an increased risk of birth defects. Talk to your doctor about the risks and benefits of taking Paxlovid if you are pregnant or breastfeeding.
This medicine is not for use in women. It is not known if this medicine will harm an unborn baby. It is also not known if this medicine passes into breast milk.
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How to Read This nirmatrelvir/ritonavir vs tadalafil Comparison
nirmatrelvir/ritonavir is classified in the Antiviral (Protease Inhibitor Combination) drug class, while tadalafil sits within the PDE5 Inhibitor class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, nirmatrelvir/ritonavir has 56,802 submissions while tadalafil has 42,549. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to this combination prevents the body from clearing tadalafil, leading to much higher levels of the drug in your system.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for nirmatrelvir/ritonavir or tadalafil.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.