darunavir vs fesoterodine

According to this portal's Publishing Organization, this page was last reviewed in August 2026 against our methodology. Figures and extracts on this site, including tables above 1,000 rows when the corpus is that large, are the publisher's responsibility.

Side-by-side comparison of darunavir and fesoterodine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

major Known Drug Interaction

Urinary antispasmodics fesoterodine ↑ fesoterodine When fesoterodine is co-administered with darunavir/ritonavir, do not exceed a fesoterodine dose of 4 mg once daily.

Drug Class
darunavir HIV Protease Inhibitor
fesoterodine Anticholinergic (Overactive Bladder)
Type
darunavir Prescription
fesoterodine Prescription
Summary
darunavir

Darunavir is a medicine used to treat HIV. It belongs to a class of drugs called protease inhibitors and must be taken with ritonavir.

fesoterodine

Fesoterodine is a medicine that helps control an overactive bladder. It reduces the feeling of needing to go to the bathroom so often.

What It Treats
darunavir

Darunavir is used to treat HIV-1 infection in adults and children 3 years and older. It must be taken with ritonavir and other HIV medicines. Darunavir helps to lower the amount of HIV in your body.

fesoterodine

This medicine treats overactive bladder (OAB) in adults. OAB can cause you to feel a sudden need to urinate. It can also cause you to urinate more often than normal, and leak urine.

How It Works
darunavir

Darunavir is a protease inhibitor. It works by blocking an enzyme called protease that HIV needs to make copies of itself. This helps to slow down the spread of HIV in your body.

fesoterodine

Fesoterodine belongs to a class of drugs called anticholinergics. It works by blocking certain nerve signals to the bladder. This helps to relax the bladder muscles and reduce the urge to urinate.

Common Side Effects
darunavir
  • Diarrhea
  • Nausea
  • Rash
  • Headache
  • Abdominal pain
fesoterodine
  • Dry mouth
  • Constipation
FAERS Reports
darunavir
  • Foetal Exposure During Pregnancy 1,150
  • Drug Interaction 981
  • Pain 889
  • Emotional Distress 812
  • Anxiety 811
fesoterodine
  • Dry mouth 823
  • Fall 529
  • Tiredness 505
  • Constipation 503
  • Unable to empty bladder 502
Serious Warnings
darunavir

Darunavir can cause liver problems. Your doctor should check your liver before you start taking darunavir and during treatment. Tell your doctor right away if you have any signs of liver problems, such as yellowing of the skin or eyes.

fesoterodine

Fesoterodine can cause swelling of the face, lips, tongue, or throat. This can be life-threatening, so stop taking the medicine and get medical help right away if this happens. Fesoterodine is not recommended if you have a blockage in your bladder or have problems with food moving through your digestive system. Use with caution if you have narrow-angle glaucoma or myasthenia gravis.

Pregnancy
darunavir

Tell your doctor if you are pregnant or plan to become pregnant. The recommended dose during pregnancy is 600 mg twice daily with ritonavir 100mg and food. Women with HIV should not breastfeed because HIV can be passed to the baby through breast milk.

fesoterodine

It is not known if fesoterodine can harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if fesoterodine passes into breast milk. Talk to your doctor about the best way to feed your baby if you are taking this medicine.

Also Compare, Nearby Drugs

How to Read This darunavir vs fesoterodine Comparison

darunavir is classified in the HIV Protease Inhibitor drug class, while fesoterodine sits within the Anticholinergic (Overactive Bladder) 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, darunavir has 4,643 submissions while fesoterodine has 2,862. 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 major interaction flagged in FDA labeling, attributed to darunavir interferes with the way your body clears fesoterodine, leading to higher levels of the medication in your blood.. 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 darunavir or fesoterodine.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.