Minoxidil is the only chemical drug in the world which has significant effect on topical hair loss. The drug for internal use is used to make blood pressure lower. If it is external used with many doses, the drug will penetrate into the body through skin absorption, it may lead to headaches, and low blood pressure. If you accidentally drip it onto your face, the drops may cause excessive growth of hair on the Department. But precisely because  "Minoxidil" is the only one topical chemical drugs which can significant effect on hair loss , so a lot of hair products in the market today contain this ingredient.
Minoxidil for the potassium channel opener, can direct relaxation of vascular smooth muscle, has a strong role of the small arteries, decreased peripheral resistance, blood pressure, but had no effect on the capacitance vessels, it can promote venous return. Also, because the reflex regulation and the role of positive frequency, cardiac output and heart rate can increase, but does not cause orthostatic hypotension.
Minoxidil’s hair loss treatment mechanism is unknown, current studies suggest that minoxidil can stimulate the hair follicle epithelial cell proliferation and differentiation, promote angiogenesis, increase local blood flow, potassium ion channels open. The hair follicles into the telogen in the growing season. Absorption of topical minoxidil system very little. Clinical trials have been fully confirmed minoxidil for androgenetic alopecia, alopecia areata has a good effect, but requires long-term medication to maintain efficacy. Hair loss, the shorter the time, the smaller the area, the better the prognosis. High concentrations than low concentrations is effective, but local adverse reactions caused by more than
The role between minoxidil and hydralazine is a little similar ,but the former is much strong and durable. It has a direct effect on vascular smooth muscle, relaxation of small arteries and reduce peripheral resistance, so that the blood pressure, no significant effect on the capacitance vessels. In the step-down reflex can also be excited when leaving the sympathetic heart rate, cardiac output, increased plasma renin activity and sodium retention. Heart rate with minoxidil directly to the heart of positive inotropic effects. Partly due to its role Shuinazhuliu renin secretion, biotin in part because a direct role in the renal tubules of the renal tubular reabsorption of Na and water due to the increase. Sodium retention and cardiac output increased blood pressure can weaken the effectiveness of the product, it often is not alone with diuretics and β-blockers combined with severe hypertension. The mechanism may be metabolized in the body because minoxidil NO sulfate, which increases vascular smooth muscle cell membrane permeability to K, K to promote the outflow of cells, causing vascular smooth muscle cell membrane hyperpolarization, so that the vascular smooth muscle relaxation and drop in blood pressure.
1, The mechanism of hair growth causing by minoxidil is still not completely clear, people think that it includes a variety of ways.
One theory is that minoxidil in the hair follicle metabolism of a mountain minoxidil sulfate, the role of K channels to prevent the aggregation of cytoplasmic free Ca2. This prevents the epidermal growth factor inhibition of hair formation. Therefore, it promotes the hair growing. Another possible reason is that minoxidil make the vascular endothelial and its receptor upregulation growing
2, In the treatment of hypertension, Minoxidil is found to make the hair (beard) longer, thicker. Therefore, at present it is on the development and application, as a treatment for male pattern baldness drugs. There are reports showing that it also plays a role in the treatment of alopecia areata. It says it promote hair growth, although the exact mechanism is unclear, the vasodilator effect reminds us that it may make the hair grown by increasing the blood supply .Minoxidil does have the function to enhanced the flowing of skin blood. S
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