Minoxidil is a topical medication that’s used to treat hair loss. Along with finasteride, it’s one of the most widely used and effective treatment options for increasing hair growth and dealing with the effects of male pattern baldness.
Like all medications, minoxidil has both primary effects and side effects. For most people, the side effects of minoxidil are relatively minor. However, it’s important that you’re aware of all of
Below, we’ve listed all of the known side effects of minoxidil, as well as detailed information on how common side effects are
What Are The Side Effects of Minoxidil?
Because minoxidil is a widely used, thoroughly tested medication, its side effects are well known amongst doctors and researchers.
Depending on the formulation, the most common side effect of minoxidil is skin irritation at or near the application site. In some cases, minoxidil users can develop a skin rash or experience a mild burning feeling after using minoxidil spray or foam.
This can be a reaction to the minoxidil itself or a reaction to some of the substances commonly used in minoxidil formulas. Many minoxidil products contain propylene glycol, and alcohol, which can lead to skin rash and irritation when applied topically.
Other, less common side effects of minoxidil include:
- Facial hair growth
- Inflammation around the hair roots
- Facial swelling
- Increased hair loss
These side effects are relatively uncommon and do not affect most minoxidil users. Increased hair loss, one of the most publicized side effects of minoxidil, is often the result of hair follicles rapidly moving through the hair growth cycle and shedding before an anagen phase. This is normal as it is part of the mechanism in how minoxidil works.
There are also side effects of minoxidil that can occur from excessive use of the medication. In most cases, these side effects occur when too much minoxidil is applied at once, resulting in an overly high level of minoxidil being absorbed into the body. These side effects include:
- Irregular heartbeat
- Chest pain
- Blurred or altered vision
- Numbness of the face, hands, and feet
- Swelling of the face, hands, feet, and legs
- Rapid weight gain
If you notice any of these side effects after taking minoxidil, the best course of action is to speak to your doctor as soon as possible.
Are Minoxidil Side Effects Common?
Minoxidil is a safe, widely used medication, with numerous studies indicating that side effects are uncommon:
- One 2013 study involving hundreds of people resulted in no side effects over almost three months of minoxidil use.
- A longer
48 weekstudy shows that topical minoxidil has no systemic effects, even at a higher-than-average 5% concentration.
Of the side effects of minoxidil, the most common
Millions of men around the world use minoxidil on a daily basis to prevent hair loss and improve hair growth. On the whole, side effects are rare and minoxidil is viewed as one of the safest hair loss treatments on the market today.
Minoxidil and Pets
One point about minoxidil that’s important to note is that it can potentially be highly toxic to cats, as they lack the enzymes required to
According to the ASPCA, there were six cases between 2001 and 2014 of cats being negatively affected by exposure to minoxidil. Of these, four cats have died after exposure, while the others required aggressive treatment in order to survive.
If you have a pet cat, make sure you do not ever directly apply minoxidil to its skin or fur. Use the minoxidil spray or foam in an isolated area (such as a bathroom, with your cat in a separate room) and keep minoxidil products stored inside a safe area that’s out of reach of your pets.
This article was reviewed by Ho Anh, MD.
Important Safety Information
IMPORTANT SAFETY INFORMATION
Finasteride is for use by MEN ONLY and should NOT be used by women or children.
Read this Patient Information before you start taking Finasteride and each time you get a refill. There may be new information. This information does not take the place of talking with your healthcare provider about your medical condition or treatment.
What is Finasteride?
Finasteride is a prescription medicine used for the treatment of male pattern hair loss (androgenetic alopecia).
It is not known if Finasteride works for a receding hairline on either side of and above your forehead (temporal area).
Finasteride is not for use by women and children.
Who should not take Finasteride?
Do not take Finasteride if you:
- are pregnant or may become pregnant. Finasteride may harm your unborn baby.
- Finasteride tablets are coated and will prevent contact with the medicine during handling, as long as the tablets are not broken or crushed. Females who are pregnant or who may become pregnant should not come in contact with broken or crushed Finasteride tablets.
- If a pregnant woman comes in contact with crushed or broken Finasteride tablets, wash the contact area right away with soap and water. If a woman who is pregnant comes into contact with the active ingredient in Finasteride, a healthcare provider should be consulted. If a woman who is pregnant with a male baby swallows or comes in contact with the medicine in Finasteride, the male baby may be born with sex organs that are not normal.
are allergic to any of the ingredients in Finasteride. See the end of this leaflet for a complete list of ingredients in Finasteride.
What should I tell my healthcare provider before taking Finasteride? Before taking Finasteride, tell your healthcare provider if you:
have any other medical conditions, including problems with your prostate or liver
Tell your healthcare provider about all the medicines you take, including prescription and nonprescription medicines, vitamins, and herbal supplements.
Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.
How should I take Finasteride?
- Take Finasteride exactly as your healthcare provider tells you to take it.
- You may take Finasteride with or without food.
If you forget to take Finasteride, do not take an extra tablet. Just take the next tablet as usual.
Finasteride will not work faster or better if you take it more than once a day.
What are the possible side effects of Finasteride?
decrease in your blood Prostate Specific Antigen (PSA) levels. Finasteride can affect a blood test called PSA (Prostate-Specific Antigen) for the screening of prostate cancer. If you have a PSA test done you should tell your healthcare provider that you are taking Finasteride because Finasteride decreases PSA levels. Changes in PSA levels will need to be evaluated by your healthcare provider. Any increase in follow-up PSA levels from their lowest point may signal the presence of prostate cancer and should be evaluated, even if the test results are still within the normal range for men not taking Finasteride. You should also tell your healthcare provider if you have not been taking Finasteride as prescribed because this may affect the PSA test results. For more information, talk to your healthcare provider.
There may be an increased risk of a more serious form of prostate cancer in men taking finasteride at 5 times the dose of Finasteride.
The most common side effects of Finasteride include:
- decrease in sex drive
- trouble getting or keeping an erection
a decrease in the amount of semen
The following have been reported in general use with Finasteride:
- breast tenderness and enlargement. Tell your healthcare provider about any changes in your breasts such as lumps, pain or nipple discharge.
- decrease in sex drive that continued after stopping the medication;
- allergic reactions including rash, itching, hives and swelling of the lips, tongue, throat, and face;
- problems with ejaculation that continued after stopping medication;
- testicular pain;
- difficulty in achieving an erection that continued after stopping the medication;
- male infertility and/or poor quality of semen.
in rare cases, male breast cancer.
Tell your healthcare provider if you have any side effect that bothers you or that does not go away.
These are not all the possible side effects of Finasteride. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA1088.
How should I store Finasteride?
- Store Finasteride at room temperature between 59˚F to 86˚F (15˚C to 30˚C).
Keep Finasteride in a closed container and keep Finasteride tablets dry (protect from moisture).
Keep Finasteride and all medicines out of the reach of children.
General information about the safe and effective use of Finasteride.
Medicines are sometimes prescribed for purposes other than those listed in this Patient Information. Do not use Finasteride for a condition for which it was not prescribed. Do not give Finasteride to other people, even if they have the same symptoms you have. It may harm them.