5MG a day of oral minoxidil
Thanks for allowing me to share my experience for the use of Oral Minoxidil in the treatment of Androgenic Alopecia.
Minoxidil is a peripheral vasodilator used officially as an antihypertensive. It occurs as a white crystalline powder and is soluble in alcohol, propylene glycol and slightly soluble in water.
The chemical name is 2, 4, - pyrimidine-diamine, 6-(1- piperidinyl), 3-oxide with molecular wt. 209.25.
More than 90% of drug is absorbed from gastrointestinal tract, reaching the maximum plasma level within first hour and declining rapidly thereafter. The average half-life in humans is 4.2 hours. Approximately 90% is metabolized predominantly in Liver by conjugation with glucuronic acid, with some by conversion to more polar products. All metabolites are excreted in urine.
Minoxidil is a direct acting peripheral vasodilator capable of reducing both elevated systolic and diastolic blood pressure. It does not interfere with the vasomotor reflux and is therefore unlikely to produce orthostatic hypotension. The primary use is for the treatment of hypertension.
Dosage is usually 2.5 to 100 mg per day as a single dose for adults.
The side effect is salt and water retention, with swelling of hands and feet, face, lower legs; rapid weight gain can occur.
Cardiovascular effects including chest pain, hypotension, and fast and irregular heart beat are possible effects. Hypertrichiosis without virilism as elongation, thickening and increased pigmentation of fine body hair are seen in about 80% of users, developing within 3-6 weeks after starting the therapy. Hypertrichosis is usually first noticed on the temples, glabella, forehead or along the sideburns. Later it may extend to a back, arms, legs, and scalp. Upon discontinuation of minoxidil the growth of new hair is arrested, but 1- 6 months may be required to resume pretreatment appearance. No endocrine abnormalities have been found to explain to this abnormal hair growth.
Other effects like thrombocytopenia, nausea, vomiting are uncommon. Breast tenderness occurs in less than 1%. Allergic rashes, blurred vision; flushing of the skin; headache; decreased sexual desire or impotence; numbness or tingling in the hands, feet or face have all been reported.
Contraindication
Minoxidil should not be used in Pheochromocytoma or those who are sensitive to the components of the preparations. It may produce pericardial effusion and occasional tamponade. Angina pectoris may be exacerbated. Full details of the drug usage and side effects may be found in the PDR.
Minoxidil may pass from mother to the child through breast milk. Therefore, women who are pregnant and breast feeding should not useminoxidil.
When I started my private practice 20 years ago, I have seen a large number of patients who were taking oral minoxidil other thanminoxidil lotion from other physicians and some patients even took on their own. I was entirely against taking oral minoxidil since it is not approved by the FDA and encouraged those patients to change to minoxidil lotion only, in fear of the side effects from oral minoxidil. After many years of practice, I have realized the remarkable effect on hair growth from oral minoxidil compared with the lotion. In many patients the result has changed from minimal hair over the scalp i.e. miniaturized hair to the cosmetic fullness of hair i.e. more terminal hair growth over both the front and the crown areas. Some have responded only at the crown but not at the front; also, there were patients who did not respond other than hypertrichosis. I have a few patients, whom I turned them down for hair transplantation surgery since they were poor candidates’ i.e. poor donor and severe degree of hair loss. One of them took oral minoxidil on his own and I was amazed when he returned to see me in four months, his temples hair was full with moderate hair growth at the crown but not at the front and made him a candidate for hair transplantation. Please see the attached photograph below. I did two sessions of hair transplant surgery on him and he was happy with the final results.
I prescribed oral minoxidil for hair loss treatment in less than 1% of patients in my practice over past 20 years. These are those hopeless patients who have the hair loss problem with no response from finasteride, dutasteride and minoxidil lotion but the patient wants to have some treatment option to treat the hair loss. I use it with caution, since there is no study regarding the dosage and safety in treating androgenic alopecia.
I do not prescribe this medicine to patients who are known to have cardiovascular disease, history of deranged blood pressure, liver and kidney dysfunction.
What is the optimal dose of oral minoxidil for the hair growth with minimal side effects?
I have learned from other physicians, who have prescribed minoxidil extensively to treat androgenic alopecia and was informed that 5 mg daily was enough to stimulate the hair growth without any effect on blood pressure and heart rate. One of my patients, who took oralminoxidil tablet and lives close by the clinic, came to the clinic twice a day for blood pressure monitoring for one month and all the reading were within the normal limits of his baseline; therefore, I am no longer monitoring the blood pressure as often as I did in the past. I have been using 5 mg daily for years and in some patient taken a low dose such as 2.5 mg tab per day or 5mg every other day still reported significant hair growth and stopped the hair loss to his satisfaction.
The most common side effect in my practice was puffy eyelids, leg swelling. Similar to any other forms of hair growth product, the gain hair will shed in 3-4 months on stopping the pill. This oral form should not be used in women due to hypertrichosis, it may persist in cases even on discontinuing the drug.
All of my patients were informed that the US FDA did not approve the use of oral minoxidil for hair growth and they have to take at their own risk, after understanding the risk and complications of the drug. I believe all the drug have side effects whether they are finasteride, dutasteride, spironolactone or dianee (for female hair loss). The long term treatment with oral minoxidil has more benefit than the chances of over said side effects at the low dose 2.5 - 5 mg once daily needs to be further studied. I advise the patient once the hair loss has stopped and experienced hair gained to stop oral minoxidil and switch back to minoxidil lotion for the long term maintenance usage. However, most of the patients did not want to switch to minoxidil lotion since there was no side effect noted. In some patient who switched to minoxidil lotion reported progressive hair loss.
I did not prescribe the diuretic as a routine since most of patients who experience water retention, refused to continue with this drug.Publications from Upjohn explicitly stated that a diuretic "must be" taken in conjunction with Loniten in most cases. The rationale is that while Loniten lowers blood pressure, your body's defense mechanism will automatically return your blood pressure to the original elevated level. Your body accomplishes that by retaining water and salt so that there will be more fluid to pump throughout the body. So in order for Loniten to be safe to consume, it is necessary to use a diuretic medication to remove excess water and salt from your body. Spironolactone is a natural choice for most hair loss sufferers since not only is Spironolactone a diuretic, it is also a potent anti-androgen.
In conclusion, only few percentage of the bald population in the world approaches the hair restoration clinics for the solution for hair loss. Of these there are many people who have marked social and emotional impact of hair loss in their lives thus, affecting their psychology. Most of these patients are very well benefited by the treatments like topical minoxidil, oral finasteride and the currently available artistic hair transplant surgeries offered by the clinics.
However there are number of patients, who are poor candidates for the hair transplant as they have poor donor area i.e. small donor area, thinning over donor area or have poor quality (more miniaturization at donor site) with large area of baldness Norwood-Class VII and searching for any possible hope that might improve their hair loss. These patients need to be emphasize regarding the side effects of oral minoxidiland with no FDA approval for hair loss indication. If patient consent's for this treatment, we propose to these terminal hair loss but high hoping patient that they might get benefit from opting to the oral minoxidil as the last sort of therapy till further new drug is available.
Best regards,
D. Pathomvanich MD FACS
