Hairgrow

Approved Indications

• Androgenetic Alopecia (Pattern Hair Loss)
• Men: Treatment of male pattern hair loss (vertex and mid-scalp area).
• Women: Treatment of female pattern hair loss (diffuse thinning on the crown).
• Severe Hypertension (Oral Formulation Only)
  Indicated for the treatment of refractory hypertension in adults and children ≥12 years, especially when other antihypertensives have failed or are contraindicated.

Clinically Accepted Off-label Uses

• Alopecia Areata (Topical):
  Sometimes used in combination with corticosteroids or immunotherapy.
• Chemotherapy-Induced Alopecia:
  Investigated for prevention or reversal of hair loss.
• Beard and Eyebrow Enhancement:
  Off-label cosmetic use in adults for stimulating beard and eyebrow growth.

Topical Minoxidil (Hair Loss)

Adults

• 2% Solution:
  Apply 1 mL to the affected scalp area twice daily (every 12 hours).
• 5% Foam or Solution:
  Apply half a capful (foam) or 1 mL (solution) twice daily in men, once daily in women (as per product labeling).
• Route: Topical (scalp only).
• Duration: At least 4 months of continuous use to assess efficacy; discontinuation leads to hair loss recurrence.

Pediatrics

• Not approved for hair loss in children under 18 years.

Oral Minoxidil (Hypertension)

Adults

• Initial dose: 5 mg once daily
• Usual maintenance dose: 10–40 mg daily, in single or divided doses
• Maximum dose: 100 mg/day

Pediatrics (≥12 years)

• Initial dose: 0.2 mg/kg once daily
• Maintenance: Adjust gradually based on response; max 50 mg/day

Special Populations

• Renal Impairment: Use with caution; risk of fluid retention.
• Hepatic Impairment: No specific adjustments, but monitor for hemodynamic effects.
• Elderly: Initiate at lower end of dosing range.

Minoxidil acts through different mechanisms depending on its route of administration. Orally, minoxidil is a direct arteriolar vasodilator that opens ATP-sensitive potassium channels in vascular smooth muscle, leading to membrane hyperpolarization, decreased calcium influx, and smooth muscle relaxation, thereby reducing peripheral vascular resistance and lowering blood pressure. Topically, the exact mechanism for hair growth is not fully understood, but it is believed to enhance hair follicle vascularity, stimulate prolongation of the anagen (growth) phase, and possibly promote follicular size and diameter. It also increases local blood flow to hair follicles and may stimulate dermal papilla cell activity.

Oral Minoxidil

• Absorption: Rapid and nearly complete oral absorption.
• Bioavailability: ~90%
• Onset of antihypertensive effect: 30 minutes to 1 hour
• Peak effect: 2–4 hours
• Distribution: Widely distributed; does not bind significantly to plasma proteins.
• Metabolism: Hepatically metabolized to inactive metabolites via conjugation (sulfate conjugation).
• Half-life: 4.2 hours (parent drug); antihypertensive effect may last up to 24 hours
• Excretion: Primarily renal (as metabolites)

Topical Minoxidil

• Systemic absorption: ~1.4% (2% solution), ~5% (5% foam/solution)
• Minimal systemic effects when used as directed

• Pregnancy:
  FDA Pregnancy Category C (oral form) – Risk cannot be ruled out. Teratogenic effects observed in animals at high doses. Use only if potential benefit justifies potential risk to fetus.
• Lactation:
  Minoxidil is excreted in breast milk (oral form). Topical absorption is minimal, but use during breastfeeding is not recommended without medical advice due to theoretical risk of systemic absorption and effects on the infant.

• Primary Class:
• Topical: Hair growth stimulant
• Oral: Antihypertensive agent
• Subclass: Direct-acting peripheral vasodilator (oral)

• Known hypersensitivity to minoxidil or any component of the formulation
• Pheochromocytoma (oral use is contraindicated due to risk of hypertensive crisis)
• Untreated or poorly controlled congestive heart failure (oral)

• Topical Use:
• Do not apply to broken, inflamed, or infected scalp.
• Avoid contact with eyes, mucous membranes, or other parts of the body.
• Oral Use:
• Must be used with a beta-blocker and a diuretic to prevent reflex tachycardia and fluid retention.
• May cause pericardial effusion or tamponade—monitor closely in patients with renal impairment or cardiovascular disease.
• Risk of hypertrichosis (unwanted hair growth), particularly in women.
• Monitor for fluid retention, weight gain, and edema.
• Pediatric Use:
  Safety and efficacy not established for topical use in children. Oral form only approved in those ≥12 years with severe hypertension.

Topical Minoxidil

Common

• Scalp irritation (itching, burning, scaling)
• Unwanted facial hair growth
• Temporary shedding (initial phase)

Rare/Serious

• Allergic contact dermatitis
• Dizziness, chest pain (from systemic absorption)
• Hypotension (very rare)

Oral Minoxidil

Common

• Fluid retention, edema
• Reflex tachycardia
• Hypertrichosis (up to 80% of users)
• Headache

Serious

• Pericardial effusion, pericarditis
• ECG changes
• Severe hypotension
• Myocardial ischemia in predisposed individuals

• Beta-blockers (e.g., propranolol): Required to offset reflex tachycardia with oral minoxidil.
• Loop diuretics (e.g., furosemide): Required to control fluid retention.
• Other antihypertensives: Additive hypotensive effects possible—monitor blood pressure closely.
• Topical corticosteroids or tretinoin (used with topical minoxidil): May increase minoxidil absorption and systemic side effects.
• Systemic absorption enzyme involvement: Does not involve CYP450 metabolism.

• Hypertension Guidelines (AHA/ACC 2022):
  Oral minoxidil remains a reserved option for treatment-resistant hypertension after failure of multiple agents.
• AAD Clinical Guidance (2023):
  Topical minoxidil remains first-line therapy for androgenetic alopecia, including 2% for women and 5% for men.
• Dermatologic Use Expansion (2023–2024):
  Topical minoxidil is increasingly used off-label for beard and eyebrow enhancement, though not FDA-approved for these uses.

• Topical Solution/Foam:
• Store at 20°C to 25°C (68°F to 77°F)
• Protect from heat, moisture, and open flame (foam is flammable).
• Keep container tightly closed.
• Do not freeze.
• Oral Tablets:
• Store at 20°C to 25°C (68°F to 77°F)
• Protect from moisture and light.
• Dispense in a tight, light-resistant container.