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chlorthalidone vs fosinopril

Side-by-side comparison of chlorthalidone and fosinopril. 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

In separate single or multiple dose pharmacokinetic interaction studies with chlorthalidone, nifedipine, propranolol, hydrochlorothiazide, cimetidine, metoclopramide, propantheline, digoxin, and warfarin, the bioavailability of fosinoprilat was not altered by coadministration of fosinopril with any one of these drugs.

Recommendation: You can generally take these together without adjusting the dose, though your doctor will monitor your response.

Drug Class
chlorthalidone Thiazide-Like Diuretic
fosinopril ACE Inhibitor
Type
chlorthalidone Prescription
fosinopril Prescription
Summary
chlorthalidone

Chlorthalidone is a water pill that helps lower blood pressure and reduce swelling. It works by helping your kidneys remove extra salt and water from your body.

fosinopril

Fosinopril is a medicine that lowers blood pressure. It can also help manage heart failure.

What It Treats
chlorthalidone

This medicine treats high blood pressure, either alone or with other drugs. It also helps with swelling from heart failure, liver problems, or kidney problems. Sometimes, it's used for swelling caused by steroid or estrogen treatments.

fosinopril

Fosinopril is used to treat high blood pressure. It can be used alone or with a water pill (diuretic). Fosinopril also helps manage heart failure when used with other medicines.

How It Works
chlorthalidone

Chlorthalidone is a diuretic, which means it helps your body get rid of extra fluid. It works by acting on your kidneys to increase the amount of salt and water that you pass in your urine. This helps to lower your blood pressure and reduce swelling.

fosinopril

Fosinopril belongs to a class of drugs called ACE inhibitors. It works by blocking a substance in your body that tightens blood vessels. This helps your blood vessels relax and lowers your blood pressure.

Common Side Effects
chlorthalidone
  • Loss of appetite
  • Upset stomach
  • Nausea
  • Vomiting
  • Cramps
fosinopril
  • Cough
  • Dizziness
  • Nausea
  • Vomiting
FAERS Reports
chlorthalidone
  • Tiredness 861
  • Feeling sick to your stomach 704
  • Loose stools 643
  • Feeling lightheaded 563
  • Aches 541
fosinopril
  • Tiredness 239
  • Diarrhea 232
  • Difficulty breathing 210
  • Feeling sick to your stomach 205
  • Feeling lightheaded 180
Serious Warnings
chlorthalidone

If you have kidney problems where you aren't producing urine, you should not take this medicine. Also, if you are allergic to chlorthalidone or other sulfa drugs, avoid this medication.

fosinopril

Fosinopril can harm your unborn baby, even causing death. Stop taking fosinopril as soon as you know you are pregnant.

Pregnancy
chlorthalidone

Using water pills when you are otherwise healthy during pregnancy is not a good idea and could be risky for you and your baby. If you have swelling during pregnancy, try raising your legs and wearing support hose first. Talk to your doctor before taking this medicine while pregnant.

fosinopril

Do not take fosinopril if you are pregnant. It can cause serious harm or death to your unborn baby. Talk to your doctor about other blood pressure medicines if you are breastfeeding.

Also Compare, Nearby Drugs

How to Read This chlorthalidone vs fosinopril Comparison

chlorthalidone is classified in the Thiazide-Like Diuretic drug class, while fosinopril sits within the ACE 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, chlorthalidone has 3,312 submissions while fosinopril has 1,066. 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 taking these medications together does not affect the amount of active medicine that enters your body.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between chlorthalidone and fosinopril - always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.