Effect of minoxidil on hair loss

# What is minoxidil? Minoxidil is a locally (topically) applied medication that is mainly used to treat hair loss. Originally developed as an oral medication for the treatment of high blood pressure, the effect of minoxidil on hair growth was discovered by chance when increased hair growth (hypertrichosis) was observed in patients. Minoxidil was subsequently approved as a solution and foam for topical use in androgenetic alopecia, a form of hereditary hair loss. The exact mechanism by which minoxidil promotes hair growth is not fully understood. However, it is assumed that minoxidil improves blood flow to the hair follicles by dilating the blood vessels (vasodilation), thus optimizing the supply of nutrients and oxygen to the hair follicles. This improved microcirculation can stimulate hair growth and slow down the progression of hair loss. Minoxidil can also prolong the anagen phase of the hair cycle, i.e. the phase in which hair is actively growing. Minoxidil is approved for both men and women to treat hair loss, but studies show that its effectiveness can vary greatly from individual to individual. Some of the differences in efficacy may be due to genetic differences between individuals, particularly genes involved in biotransformation and the body's response to minoxidil. # Duration of effect and application The effect of Minoxidil is not immediate, visible results are usually only achieved after several months of continuous use. It is recommended to apply Minoxidil twice a day to the affected areas of the scalp. Increased hair loss may occur during the first few weeks of use, which is seen as a sign that the medication is affecting the hair cycle and replacing old, inactive hair before new, stronger hair grows back. This so-called "shedding effect" is temporary and should not be interpreted as a sign of a lack of efficacy. > ## Good to know > Minoxidil is the only non-prescription medication approved in low concentrations that has been clinically proven to reduce hair loss and promote hair growth. # Side effects and tolerability Topical application of minoxidil is generally well tolerated, but some people may experience side effects. The most common include skin irritations such as redness, itching or burning at the application site. In rare cases, allergic reactions may also occur. To improve tolerability, it is important to apply the product only to the scalp and avoid contact with the face or other areas of skin, as this can lead to unwanted hair growth in these areas. # Long-term effects and discontinuation Minoxidil is not a cure for hair loss, but a therapy that must be continued on an ongoing basis in order to maintain success. Stopping minoxidil usually leads to renewed hair loss within a few months and the loss of the hair gained. Therefore, individuals who choose to use minoxidil should be prepared to continue treatment long-term to maximize the benefits and avoid setbacks. # What do genetics have to do with it? The genetic link between minoxidil and hair loss is highlighted by the SNP rs9282861 (also known as rs1042028) in the SULT1A1 gene. The SULT1A1 gene codes for the enzyme sulfotransferase 1A1, which plays a central role in the sulfation of minoxidil. Sulfation is a biochemical process in which a sulfate group is attached to the minoxidil molecule, converting the drug into its active form. This activation is crucial as only sulphated minoxidil can develop its effect in the hair follicles and stimulate hair growth. However, the efficiency of this enzymatic conversion varies from individual to individual and is influenced by genetic differences in the SULT1A1 gene. The SNP rs9282861 alters a single nucleotide position in the DNA sequence of the gene and has two possible variants, C and T. These variations lead to differences in the activity of the SULT1A1 enzyme, which in turn affects the body's ability to effectively activate minoxidil. This is an important factor that explains why some people respond better to treatment with minoxidil, while others experience little or no improvement.