Oct 15, 2019 | By Dr. Sangay Bhutia (Hair Transplant Specialist in Delhi)
Most persons who experience hair loss must have heard about minoxidil and good number of patients must have used also. It is because it is FDA approved medicine for hair loss and it is readily available over the counter (OTC) medicine that means prescription is not required to get this medicine.
It was originally used to treat patients having high blood pressure but when applied topically, it is used for treatment of hair loss. It helps in promoting hair growth in patients with androgenetic alopecia.
How it works for hair growth?
Minoxidil shortens telogen phase leading to the entry of resting hair follicles into anagen phase. This may cause follicles in telogen phase to shed, which are then replaced by thicker hairs in a new anagen phase. In other words it lengthens the growth phase of the hair cycle and thereby improve the length and diameter of the hair.
The actual mechanism is not fully understood. Some hypothesized that by opening the potassium channels it causes vasodilatation thereby providing more blood supply, oxygen and nutrition to the hair follicle. It acts on the potassium channels in the dermal papilla of hair and also directly stimulates the growth of follicle and the dermal papilla cells.
How to use?
It is available in 2% and 5% concentration in lotion as well as in form of foam. 5% lotion formulation is more effective but it can cause irritation of the scalp owing to the presence of propylene glycol. The foam does not have the solvent propylene glycol so it does not have that feeling of greasy hair. This makes foam a favorable choice for the patients.
Minoxidil is to be applied on scalp once or twice daily and the medicine should be applied on scalp and not the hairs. 2% minoxidil lotion is generally used in females alopecia.
The result in form of hair regrowth is seen after few months of use and it has to be used continuously otherwise when it is discontinued then the condition of hair loss reaches the pre-treatment state after 3-4 months. That means all the benefit achieved with the treatment is lost once the medicine is stopped.
The common side effects are redness on the area, irritation and itching on the scalp, Dryness and flaky scalp. These are due to the presence of alcohol and propylene glycol in the topical formulations.
There may be unwanted hair growth on the face when applied accidentally. Some patients may get allergy or hypersensitivity reaction to minoxidil in form of swelling or hives. Severe allergy may lead to breathing difficulty, tightness in chest, dizziness, tachycardia.
Temporary hair loss also called minoxidil induced hair loss is also a common side effect of this therapy.