Hypertrichosis minoxidil

Potassium channel openers Hypertrichosis (minoxidil) lupus-like reactions and pedal edema (hydralazine)... 

Tachycardia, palpitations, angina, and edema are observed when doses of 3 blockers and diuretics are inadequate. Headache, sweating, and hypertrichosis, which is particularly bothersome in women, are relatively common. Minoxidil illustrates how one person s toxicity may become another person s therapy. Topical minoxidil (as Rogaine) is used as a stimulant to hair growth for correction of baldness. 

Minoxidil Metabolite opens channels in vascular smooth muscle Minoxidil Hypertrichosis... 

VASODILATOR ANTIHYPERTENSIVES CICLOSPORIN 1. Co-administration of bosentan and cidosporin leads to t bosentan and 1 cidosporin levels 2. Risk of hypertrichosis when minoxidil given with cidosporin 3. t sitaxentan levels 1. Additive effect both drugs inhibit the bile sodium export pump, which is associated with hepatotoxicity 2. Additive effect 3. Uncertain 1. Avoid co-administration of bosentan and cidosporin 2. Warn patients of the potential interaction 3. Avoid co-administration... 

Minoxidil is a vasodilator selective for arterioles rather than for veins, similar to diazoxide and hydralazine. Like the former, it acts through its sulphate metabolite as an ATP-dependent potassium channel opener. It is highly effective in severe hypertension, but causes increased cardiac output, tachycardia, fluid retention and hypertrichosis. The hair growth is generalised and although a cosmetic problem in women, it has been exploited as a topical solution for the treatment of baldness in men. 

A particular feature of minoxidil is excessive hair growth (7), which occurs in about 70% of patients who take oral minoxidil, usually within 2 months of the start of therapy. Severe hypertrichosis, unacceptable even to men, has comphcated the otherwise successful antihypertensive treatment of six patients after renal transplantation, for which ciclosporin was also used. Since hypertrichosis has also been described with ciclosporin, there may be an additive pharmacodynamic interaction (8). 

Topical minoxidil has been used to treat women with androgenic alopecia. Severe hypertrichosis of the face and the hmbs occurred in three women after 2-3 months of treatment with 5% topical minoxidil (9). The hypertrichosis disappeared from the face and arms within 1-3 months of withdrawal and from the legs after 4-5 months. 

Toriumi DM, Konior RJ, Berktold RE. Severe hypertrichosis of the external ear canal during minoxidil therapy. Arch Otolaryngol Head Neck Surg 1988 114(8) 918-19. 

Sever MS, Sonmez YE, Kocak N. Limited use of minoxidil in renal transplant recipients because of the additive side-effects of cyclosporine on hypertrichosis. Transplantation 1990 50(3) 536. 

Peluso AM, Misciali C, Vincenzi C, Tosti A. Diffuse hypertrichosis during treatment with 5 % topical minoxidil. Br J Dermatol 1997 136(l) 118-20. 

Nicorandil, like minoxidil, appears to enhance the incorporation of cysteine into hair shafts (22). However, hypertrichosis has not been reported. 

Adverse Effects. The side effects of topical minoxidil are mainly local, caused by skin irritation and contact dermatitis. Systemic side effects are uncommon because of limited percutaneous absorption, but diffuse hypertrichosis of the face and limbs has been reported with the 5% solution and was attributed to systemic absorption of the drug (84). Although topical minoxidil does not change blood pressure in healthy subjects, it increases heart rate by 3-5 beats/min and slightly increases the left ventricular end-diastolic volume, cardiac output, and left ventricular mass (85). These effects are not considered clinically significant, and the potential for cardiovascular side effects is very low. 

One side effect should be mentioned hypertrichosis. Within 2 months of initiating therapy increased hair growth begins on the face and the palms of the hands. It affects three-fourths of patients and may have psychological ramifications in women and children. The effects may persist for several months after the drug is withdrawn. Attempts to utilize this side effect to restore hair growth in cases of baldness with topical preparations of minoxidil (Rogaine) have succeeded. 

ADVERSE EFFECTS AND PRECAUTIONS The adverse effects of minoxidil can be severe and are divided into three major categories fluid and salt retention, cardiovascular effects, and hypertrichosis. 

Minoxidil (rogaine) was first developed as an antihypertensive agent (see Chapter 32) and was noted to be associated with hypertrichosis in some patients. A topical formulation of minoxidil... 

The concurrent use of ciclosporin and minoxidil can cause excessive hairiness (hypertrichosis). 

Six male kidney transplant patients taking ciclosporin (blood levels of 100 to 200 nanograms/mL) were given methyidopa, a diuretic and minoxidil 15 to 40 mg daily for intractable hypertension. After 4 weeks of treatment all of them complained of severe and unpleasant hypertrichosis (excessive hairiness). Two months after stopping the minoxidil the hypertrichosis had significantly improved. Both ciclosporin and minoxidil cause hypertrichosis and it would seem that their effects may be additive. The authors of the report point out that this is not a life-threatening problem, but it limits the concurrent use of these drugs in both men and women. ... 

With continued use of minoxidil, over 50% of the patients show a hypertrichosis, females often a marked hirsutism (125, 127, 128 =, 129, 130 -, 131 ). CompaJints of paraesthesia are common during prolonged use. The extent, severity and frequency of occurrence of side effects with minoxidil are still unknown. 

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