Minoxidil may increase chest pain (angina) or cause other heart problems. It is important that you keep all appointments with your doctor so that you can be monitored for any symptoms or changes. If chest pain occurs or worsens while you are taking this medication, call your doctor immediately. Your doctor may prescribe other medicines as part of your minoxidil therapy. Do not stop taking these medications unless your doctor tells you to do so.
Minoxidil is used with other drugs to treat high blood pressure. It works by relaxing the blood vessels so that blood can flow more easily through the body.
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
Minoxidil comes as a tablet to take by mouth. It usually is taken once or twice a day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take minoxidil exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Minoxidil controls high blood pressure but does not cure it. Continue to take minoxidil even if you feel well. Do not stop taking minoxidil without talking to your doctor.
Before taking minoxidil,
- tell your doctor and pharmacist if you are allergic to minoxidil or any other drugs.
- tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially other medications for high blood pressure, diuretics ('water pills'), guanethidine, and vitamins.
- tell your doctor if you have or have ever had heart disease, a heart attack, pheochromocytoma, or kidney disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking minoxidil, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking minoxidil.
- you should know that this drug may make you drowsy. Do not drive a car or operate machinery until you know how it affects you.
- ask your doctor about the safe use of alcohol while you are taking minoxidil. Alcohol can make the side effects from minoxidil worse.
Your doctor may prescribe a low-salt or low-sodium diet. Follow these directions carefully.
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Minoxidil may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- increase in size or darkness of fine body hair
- breast tenderness
If you experience any of the following symptoms, or those listed in the IMPORTANT WARNING section, call your doctor immediately:
- fast heartbeat
- swollen ankles or feet
- unexplained weight gain
- difficulty breathing
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at Web Site] or by phone [1-800-332-1088].
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly to determine your response to minoxidil. Your doctor may order other tests such as EKG (electrocardiogram) to monitor your heart function.
Your doctor may ask you to check your pulse (heart rate) daily. Ask your doctor or pharmacist to teach you how to do this. Call your doctor if your heart rate increases by more than 20 beats per minute while at rest.
Weigh yourself every day. Call your doctor if you experience rapid weight gain.
Do not let any one else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Last Reviewed: September 1, 2010.