Drug class
Arteriolar Vasodilator [EPC]
Uses
Use to regrow hair on the top of the scalp (see pictures on side of this carton)
Boxed warning
WARNINGS Minoxidil tablets contain the powerful antihypertensive agent, minoxidil, which may produce serious adverse effects. It can cause pericardial effusion, occasionally progressing to tamponade, and angina pectoris may be exacerbated. Minoxidil should be reserved for hypertensive patients who do not respond adequately to maximum therapeutic doses of a diuretic and two other antihypertensive agents. In experimental animals, minoxidil caused several kinds of myocardial lesions as well as other adverse cardiac effects (see Cardiac Lesions in Animals ). Minoxidil must be administered under close supervision, usually concomitantly with therapeutic doses of a beta-adrenergic blocking agent to prevent tachycardia and increased myocardial workload. It must also usually be given with a diuretic, frequently one acting in the ascending limb of the loop of Henle, to prevent serious fluid accumulation. Patients with malignant hypertension and those already receiving guanethidine (see WARNINGS ) should be hospitalized when minoxidil is first administered so that they can be monitored to avoid too rapid, or large orthostatic, decreases in blood pressure.
Warnings
Warnings For external use only. Extremely Flammable: Avoid fire, flame, or smoking during and immediately following application. Do not use if your degree of hair loss is different than that shown on side of this carton because this product may not work for you you have no family history of hair loss your hair loss is sudden and/or patchy your hair loss is associated with childbirth you do not know the reason for your hair loss you are under 18 years of age. Do not use on babies and children. your scalp is red, inflamed, infected, irritated, or painful you use other medicines on the scalp Ask a doctor before use if you have heart disease When using this product do not use more than directed do not apply on other parts of the body avoid contact with the eyes. In case of accidental contact, rinse eyes with large amounts of cool tap water. some people have experienced changes in hair color and/or texture it takes time to regrow hair. Results may occur at 3 months with once-daily use. For some women, you may need to use this product once a day for at least 6 months before you see results. the amount of hair regrowth is different for each person. This product will not work for all women. Stop use and ask a doctor if chest pain, rapid heartbeat, faintness, or dizziness occurs sudden, unexplained weight gain occurs your hands or feet swell scalp irritation or redness occurs unwanted facial hair growth occurs you do not see hair regrowth in 6 months May be harmful if used when pregnant or breast-feeding. Keep out of reach of children. If swallowed, get medical help or contact a Poison Control Center right away. (1-800-222-1222)
Contraindications
CONTRAINDICATIONS Minoxidil tablets are contraindicated in pheochromocytoma, because it may stimulate secretion of catecholamines from the tumor through its antihypertensive action. Minoxidil is contraindicated in those patients with a history of hypersensitivity to any of the components of the preparation.
Overdose
OVERDOSAGE There have been only a few instances of deliberate or accidental overdosage with minoxidil tablets. One patient recovered after taking 50 mg of minoxidil together with 500 mg of a barbiturate. When exaggerated hypotension is encountered, it is most likely to occur in association with residual sympathetic nervous system blockade from previous therapy (guanethidine-like effects or alpha-adrenergic blockage), which prevents the usual compensatory maintenance of blood pressure. Intravenous administration of normal saline will help to maintain blood pressure and facilitate urine formation in these patients. Sympathomimetic drugs such as norepinephrine or epinephrine should be avoided because of their excessive cardiac stimulating action. Phenylephrine, angiotensin II, vasopressin, and dopamine all reverse hypotension due to minoxidil, but should only be used if underperfusion of a vital organ is evident. Radioimmunoassay can be performed to determine the concentration of minoxidil in the blood. At the maximum adult dose of 100 mg/day, peak blood levels of 1641 ng/mL and 2,441 ng/mL were observed in two patients, respectively. Due to patient-to-patient variation in blood levels, it is difficult to establish an overdosage warning level. In general, a substantial increase above 2,000 ng/mL should be regarded as overdosage, unless the physician is aware that the patient has taken no more than the maximum dose. Oral LD 50 in rats has ranged from 1,321 - 3,492 mg/kg; in mice, 2,456 - 2,648 mg/kg.
Drug interactions
4. Drug Interactions See “Interaction with Guanethidine” under WARNINGS.
Dosage & administration
Directions • Apply 1ml directly to the treated scalp area. • Massage into the scalp and wash hands thoroughly. • Visible results may take 2 months with twice-daily application. • For some, at least 4 months of use may be needed. Effectiveness varies.
Active ingredient
Active Ingredient Minoxidil 5%
Inactive ingredient
Inactive ingredients alcohol, propylene glycol, purified water
Side effects
ADVERSE REACTIONS 1. Salt and Water Retention (see WARNINGS: Concomitant Use of Adequate Diuretic is Required) - Temporary edema developed in 7% of patients who were not edematous at the start of therapy. 2. Pericarditis, Pericardial Effusion and Tamponade ( see WARNINGS) . 3. Dermatologic - Hypertrichosis-Elongation, thickening, and enhanced pigmentation of fine body hair are seen in about 80% of patients taking minoxidil tablets. This develops within 3 to 6 weeks after starting therapy. It is usually first noticed on the temples, between the eyebrows, between the hairline and the eyebrows, or in the side-burn area of the upper lateral cheek, later extending to the back, arms, legs, and scalp. Upon discontinuation of minoxidil, new hair growth stops, but 1 to 6 months may be required for restoration to pretreatment appearance. No endocrine abnormalities have been found to explain the abnormal hair growth; thus, it is hypertrichosis without virilism. Hair growth is especially disturbing to children and women and such patients should be thoroughly informed about this effect before therapy with minoxidil is begun. Allergic - Rashes have been reported, including rare reports of bullous eruptions, toxic epidermal necrolysis, and Stevens - Johnson Syndrome. 4. Hematologic - Thrombocytopenia and leukopenia (WBC<3000/mm 3 ) have rarely been reported. 5. Gastrointestinal - Nausea and/or vomiting has been reported. In clinical trials the incidence of nausea and vomiting associated with the underlying disease has shown a decrease from pretrial levels. 6. Miscellaneous - Breast tenderness - This developed in less than 1% of patients. 7. Altered Laboratory Findings - (a) ECG changes - Changes in direction and magnitude of the ECG T-waves occur in approximately 60% of patients treated with minoxidil. In rare instances a large negative amplitude of the T-wave may encroach upon the S-T segment, but the S-T segment is not independently altered. These changes usually disappear with continuance of treatment and revert to the pretreatment state if minoxidil is discontinued. No symptoms have been associated with these changes, nor have there been alterations in blood cell counts or in plasma enzyme concentrations that would suggest myocardial damage. Long-term treatment of patients manifesting such changes has provided no evidence of deteriorating cardiac function. At present the changes appear to be nonspecific and without identifiable clinical significance. (b) Effects of hemodilution-hematocrit, hemoglobin and erythrocyte count usually fall about 7% initially and then recover to pretreatment levels. (c) Other - Alkaline phosphatase increased varyingly without other evidence of liver or bone abnormality. Serum creatinine increased an average of 6% and BUN slightly more, but later declined to pretreatment levels.