Generic name: Fosinopril sodium.

Monopril is an angiotensin-converting enzyme (ACE) inhibitor. It works to reduce blood pressure by preventing angiotensin from converting into a more potent enzyme that increases salt and water retention. 

Quick Facts About Monopril


Used to treat high blood pressure.

Monopril Dosage

Take one hour before meals or with food if you experience stomach irritation. May take weeks to observe results if taking for high blood pressure; must continue to take even if you feel better. If stopped abruptly, may cause increase in blood pressure.

  • Usual adult dose: 10 milligrams taken once per day. After blood pressure adjusts, 20 to 40 milligrams per day in a single dose. Diuretics should be stopped prior to Monopril therapy; otherwise, doctor may give initial dose of I0 milligrams. Seniors — dose prescribed according to individual needs.
  • Usual child dose: not generally prescribed for children.
  • Missed dose: take as soon as possible, unless almost time for next dose. In that case, do not take missed dose; go back to regular schedule.

Monopril Side Effects

Overdose symptoms:

sudden drop in blood pressure. If you suspect an overdose, immediately seek medical attention.

More common side effects: cough, diarrhea, dizziness, fatigue, headache, nausea, vomiting.

Less common or rare Monopril side effects: abdominal pain, anaphylaxis (severe allergic reaction), changes in appetite and weight, changes in sexual performance, confusion, constipation, decreased sex drive, drowsiness, dry mouth, excessive sweating, eye irritation, gas, heartburn, itching, kidney failure, liver failure, muscle cramps, rash, ringing in ears, skin sensitivity to sunlight, sleep disturbances, tremors, vertigo, vision disturbances, weakness, yellow eyes and skin.


Inform your doctor before combining Monopril with:

antacids such as Maalox and Mylanta, Lithium, potassium preparations such as K-Ten and K-Lyte, potassium-sparing diuretics such as Moduretic and Aldactone, thiazide diuretics such as Esidrix and Diuril.

Avoid using potassium-containing salt substitutes unless directed by your doctor.

Special Cautions

ACE inhibitors have caused damage and death of fetus if used in 2nd or 3rd trimesters. If pregnant, discontinue use of this medication as soon as possible. If planning to become pregnant, discuss hazards of this medication. Appears in breast milk, could affect a nursing infant.

Dose prescribed according to individual needs for seniors.

Not generally prescribed for children.

  • Swelling of the face, lips, tongue or throat, or arms and legs or difficulty swallowing may indicate the need for emergency treatment Immediately contact your doctor.
  • If you faint during first few days of therapy, stop taking and notify your doctor at once.
  • Use with caution if on dialysis, at risk for extreme allergic reactions.
  • If sensitive to or allergic to this or similar medications, should not take.
  • Inform your doctor immediately if you develop a sore throat or fever.
  • Tell your doctor if you have kidney or liver problems, or connective tissue disease. With connective disease, may need blood tests.
  • When taken with a diuretic in high doses, may cause very low blood pressure.
  • If you have congestive heart failure, doctor should closely monitor you for the first 2 weeks, and whenever the dosage is increased.
  • Use caution to not deplete your fluids — may cause blood pressure to become dangerously low. Monitor severe diarrhea or vomiting, excessive sweating, or exercising.

Note: provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Monopril side effects, please contact your healthcare provider.