Minoxidil belongs to a group of medications known as hair regrowth treatments. It is used to treat male pattern baldness. It is not meant for baldness due to nonhereditary factors (e.g., baldness caused by illnesses such as iron deficiency or medications such as cancer chemotherapy). The foam formulation of minoxidil is also used to treat female pattern hair loss or thinning.

When applied to the scalp, it often stimulates hair growth. The exact way it works is not known, but it is thought to improve the blood flow around the hair follicle and stimulate the hair follicle to grow hair.

It usually takes at least 4 to 6 months of use for the medication to work. Hair may fall out when minoxidil is first used. This is a temporary effect of the medication. Once hair starts to grow, it will stay for as long as the medication is used. The hair will begin to fall out again a few months after the applications are stopped.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are using this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

The recommended dose is 1 mL applied twice daily to the scalp, starting in the centre of the affected area. This dose should be used no matter how large the area to which it is being applied. The maximum daily dose is 2 mL.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way you are using the medication without consulting your doctor.

The solution comes with a pump-spray applicator, and a child-resistant dropper. The spray is more convenient for applying to large areas of the scalp, while the dropper makes it easier to use on small areas of the scalp or under hair. Refer to package directions for details on the best way to apply the solution with each dosage form.

It is important that the solution stay in contact with the scalp for at least 4 hours after application. During this time, avoid activities such as swimming, showering, or physical activity that may cause excessive perspiration.

If you are washing your hair before applying the medication, use a mild shampoo. To avoid eye irritation, wash your hands well after applying this medication to the scalp. Avoid inhaling the spray mist. Do not apply this medication to any area of the body other than the scalp.

It is important to use this medication exactly as prescribed by your doctor. If you miss a dose, use it as soon as possible and continue with your regular schedule. If it is almost time for the next dose, skip the missed dose and continue with your regular dosing schedule. Do not use a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.
Store this medication at room temperature and keep it out of the reach of children.

Do not use this medication if you:

• are allergic to minoxidil or any ingredients of the solution
• are bald due to non-hereditary factors (e.g., caused by illnesses such as iron deficiency, thyroid disorders, or medications such as cancer chemotherapy)
• have hair loss associated with childbirth
• have a skin condition on the scalp (e.g., psoriasis or sunburns)
• are or may be pregnant or are nursing
• are using other skin medications or dressings on the scalp (e.g., for psoriasis)
• have shaved, broken, inflamed, irritated, infected, or severely sunburned skin on the scalp
• have untreated high blood pressure
• have recently discontinued certain medications such as birth control or cancer chemotherapy
• have certain grooming habits (e.g., cornrowing, tight ponytails)

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people using this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• backache
• changes in hair colour or texture
• cold- or flu-like symptoms (e.g., runny or stuffy nose, cough, sore throat)
• continuous itching or skin rash
• irritation, redness, dryness in the area where medication was applied
• muscle pain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• acne where medication was applied
• burning of the scalp
• changes in blood pressure
• depressed mood
• dizziness
• feeling faint
• headache
• inflammation or soreness at the hair root
• persistent local rash
• rapid heartbeat
• sudden weight gain
• swelling of the hands or feet
• temporary hair loss
• unwanted facial hair growth

Stop taking the medication and seek immediate medical attention if any of the following occur:

• chest pain
• shortness of breath or difficulty breathing

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Effectiveness: Minoxidil may not work for everyone. This medication is for the scalp of someone who has male pattern baldness or female hair loss or thinning. It has not been shown to work for someone who has a receding hairline. Shedding of hair may occur within 2 to 6 weeks of starting to use this product. If shedding persists beyond 2 weeks, contact your doctor. If you do not see any results after 6 months of using this product, contact your doctor.

Eye irritation: Minoxidil will cause irritation and burning of the eyes and nasal passages. If the medication comes in contact with the eyes, flush the eyes well with cool water.

Hair treatments: It is not known if hair colouring, perming, or relaxing agents affect this medication. To avoid irritation to the scalp, make sure this medication has been washed off the hair and scalp before using these products. Do not reapply minoxidil for 24 hours after using a chemical treatment to make sure your scalp has not been irritated by the perm or colour treatment.

Heart disease: Although this medication is intended to be used as a topical (surface only) treatment for the scalp, it may be absorbed into the bloodstream and have an effect on heart disease. People with heart disease should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pregnancy: This medication should not be used during pregnancy. If you become pregnant while taking this medication, stop taking it and contact your doctor immediately.

Breast-feeding: This medication passes into breast milk. If you are breast-feeding and are using minoxidil, it may affect your baby. Women who are breast-feeding should not use minoxidil.

Children: The safety and effectiveness of using this medication have not been established for children under 18 years of age.

Seniors: The safety and effectiveness of using this medication have not been established for men over the age of 65 years.

There may be an interaction between minoxidil topical solution and any of the following:

• anthralin
• blood-pressure-lowering medications
• cyclosporine
• other topical (applied to the skin) medications
• topical corticosteroids (e.g., betamethasone, hydrocortisone)
• tretinoin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.