Minoxidil is a clinical oral drug used to lower blood pressure, also known as long pressure idine, piperazine diamine, hypotenidine, minlohemoidine, belongs to potassium channel opening agent, can directly relax vascular smooth muscle, has a strong small artery dilation effect, reduce peripheral resistance, blood vessel dilation, blood pressure, but has no effect on volume blood vessels, so it can promote venous return. At the same time, due to the reflex regulation and positive frequency effect, cardiac output and heart rate can be increased, but it does not cause postural hypotension. It is used in the treatment of refractory hypertension and renal hypertension. It can also be used for severe hypertension with poor effect of other antihypertensive drugs, but it needs to be combined with diuretics to avoid water and sodium retention, and the combination of β-receptor blocking drugs can increase its efficacy and reduce adverse reactions. As a side effect of long-term use of minoxidil, body hair may increase slightly as the drug continues to be used, such as hair on the arms. But generally within acceptable limits. The main adverse reactions of oral administration were: weight gain and lower limb edema caused by water and sodium retention, palpitation and arrhythmia caused by reflex sympathetic nerve excitation, and hirsutism. The main adverse reactions of topical preparations include skin irritation, erythema, itching and other dermatitis reactions. Although the amount of absorption in the topical preparation is very small, it cannot be ruled out that it has an effect on the condition of patients with a history of heart disease. Patients with cerebrovascular disease, non-hypertensive heart failure, coronary heart disease, angina pectoris, myocardial infarction, pericardial effusion, renal dysfunction and other diseases must be used with caution, minoxidil allergy and pheochromocytoma patients should be contraindicated.

Application

1 A blood pressure lowering drug for refractory, primary, or renal hypertension. It is used to prevent oil alopecia and animal husbandry.

2 A blood pressure lowering drug used in the treatment of intractable, primary, or renal hypertension.

Pharmacological action

Minoxidil directly dilates the arterioles, thereby reducing blood pressure, but the exact mechanism is unknown. This product does not dilate small veins. Reduced peripheral vascular resistance leads to increased reflex heart rate and increased cardiac output. The activity of renin increased after hypotensive, which resulted in water and sodium retention. This product does not interfere with vasomotor reflex, so orthostatic hypotension does not occur. Minoxidil is a commonly used and effective drug for the treatment of hair loss, but its pharmacological action and its target cells are not very clear. Studies in recent years have shown that minoxidil may promote hair growth through the following ways.