A potent direct-acting peripheral vasodilator (vasodilator agents) that reduces peripheral resistance and produces a fall in blood pressure. (From Martindale, The Extra Pharmacopoeia, 30th ed, p371).
For the treatment of severe hypertension and in the topical treatment (regrowth) of androgenic alopecia in males and females and stabilisation of hair loss in patients with androgenic alopecia.
Minoxidil tablets should not be used to promote scalp hair growth. Only the topical form of minoxidil (Rogaine) is recommended for that use.
Minoxidil may also be used for purposes not listed in this medication guide.
Minoxidil is an orally effective direct acting peripheral vasodilator that reduces elevated systolic and diastolic blood pressure by decreasing peripheral vascular resistance. Minoxidil is also used topically to treat androgenetic alopecia.
Microcirculatory blood flow in animals is enhanced or maintained in all systemic vascular beds. In man, forearm and renal vascular resistance decline; forearm blood flow increases while renal blood flow and glomerular filtration rate are preserved. The predominant site of minoxidil action is arterial.
Venodilation does not occur with minoxidil; thus, postural hypotension is unusual with its administration. The antihypertensive activity of minoxidil is due to its sulphate metabolite, minoxidil sulfate.
Minoxidil is thought to promote the survival of human dermal papillary cells (DPCs) or hair cells by activating both extracellular signal-regulated kinase (ERK) and Akt and by preventing cell death by increasing the ratio of BCl-2/Bax.
Minoxidil may stimulate the growth of human hairs by prolonging anagen through these proliferative and anti-apoptotic effects on DPCs. Minoxidil, when used as a vasodilator, acts by opening adenosine triphosphate-sensitive potassium channels in vascular smooth muscle cells.
This vasodilation may also improve the viability of hair cells or hair follicles.
Metabolism: Approximately 90% of the administered drug is metabolized, predominantly by conjugation with glucuronic acid at the N-oxide position in the pyrimidine ring, but also by conversion to more polar products. Known metabolites exert much less pharmacologic effect than minoxidil itself.
Absorption: Minoxidil is at least 90% absorbed from the GI tract in experimental animals and man.
Half life: 4.2 hours
All medicines may cause side effects, but many people have no, or minor, side effects.Some medical conditions may interact with Minoxidil.
Tell your doctor or pharmacist if you have any medical conditions.
Side effects include cardiovascular effects associated with hypotension such as sudden weight gain, rapid heart beat, faintness or dizziness.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider.
