losartan vs rifampin

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

minor Known Drug Interaction

Substitute non-enzyme inducing therapies at least 2 weeks prior to initiation of irinotecan therapy Decrease irinotecan and active metabolite exposure Levothyroxine Decrease exposure Losartan Parent Decrease AUC by 30% Active metabolite (E3174) Decrease AUC by 40% Methadone In patients well-stabilized on methadone, concomitant administration of rifampin resulted in a marked reduction in serum methadone levels and a concurrent appearance of withdrawal symptoms.

Drug Class
losartan Angiotensin II Receptor Blocker (ARB)
rifampin Rifamycin Antibiotic
Type
losartan Prescription
rifampin Prescription
Summary
losartan

Losartan is a medicine that lowers blood pressure. It can also help prevent strokes in some people with high blood pressure and an enlarged heart.

rifampin

Rifampin is an antibiotic medicine. It fights bacteria in your body to treat infections.

What It Treats
losartan

Losartan is used to treat high blood pressure in adults and children over 6 years old. Lowering blood pressure reduces the risk of strokes and heart attacks. It is also used to treat kidney problems in people with type 2 diabetes and high blood pressure. Losartan can also reduce the risk of stroke in patients with high blood pressure and an enlarged left ventricle of the heart.

rifampin

Rifampin treats tuberculosis (TB) and helps eliminate the bacteria that cause meningitis from your nose and throat. It is important to use rifampin only for infections that are proven or strongly suspected to be caused by bacteria. This helps to prevent bacteria from becoming resistant to the medicine.

How It Works
losartan

Losartan blocks a substance in your body that tightens blood vessels. This helps blood vessels relax, which lowers blood pressure. It also helps the kidneys work better in people with diabetes.

rifampin

Rifampin works by stopping bacteria from growing and multiplying. It does this by blocking a key enzyme that the bacteria need to make proteins. This helps your body fight off the infection.

Common Side Effects
losartan
  • Dizziness
  • Upper respiratory infection
  • Nasal congestion
  • Back pain
rifampin
  • Heartburn
  • Upset stomach
  • Loss of appetite
  • Nausea
  • Vomiting
FAERS Reports
losartan
  • Fatigue 11,852
  • Diarrhoea 9,870
  • Nausea 9,207
  • Dyspnoea 8,439
  • Dizziness 7,999
rifampin
  • Drug Interaction 970
  • Drug Reaction With Eosinophilia And Systemic Symptoms 727
  • Nausea 628
  • Condition Aggravated 550
  • Pyrexia 541
Serious Warnings
losartan

Losartan can harm your unborn baby, even causing death. If you are pregnant or plan to become pregnant, tell your doctor right away. Stop taking losartan as soon as you know you are pregnant.

rifampin

Rifampin can cause liver problems. Tell your doctor right away if you have yellowing of the skin or eyes, dark urine, or stomach pain. Rifampin can also cause blood problems. Tell your doctor if you have unusual bleeding or bruising.

Pregnancy
losartan

Do not take losartan if you are pregnant. It can cause serious harm or death to the developing fetus. If you are breastfeeding, talk to your doctor about whether losartan is right for you.

rifampin

Tell your doctor if you are pregnant or plan to become pregnant. Rifampin can make birth control pills less effective, so use other forms of birth control. Talk to your doctor if you are breastfeeding.

Also Compare, Nearby Drugs

How to Read This losartan vs rifampin Comparison

losartan is classified in the Angiotensin II Receptor Blocker (ARB) drug class, while rifampin sits within the Rifamycin Antibiotic 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, losartan has 47,367 submissions while rifampin has 3,416. 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 minor interaction flagged in FDA labeling, attributed to rifampin speeds up the breakdown of losartan in your body, which lowers the amount of medicine available to work.. 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 losartan or rifampin.

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