Usage
Finasteride + Minoxidil is prescribed for androgenetic alopecia (AGA), also known as male pattern baldness and female pattern hair loss. It is classified as a hair growth stimulant. Finasteride is a 5-alpha reductase inhibitor and minoxidil is a potassium channel opener and acts as a vasodilator, though precisely how vasodilation relates to hair growth promotion is not well understood.
Alternate Names
No alternate names for the combination exist. Brand names include Hims Finasteride & Minoxidil, and other brand names may exist depending on the region and specific formulation.
How It Works
Finasteride:
- Pharmacodynamics: Finasteride inhibits the type II and III isoenzymes of 5-alpha reductase, thus blocking the conversion of testosterone to dihydrotestosterone (DHT). DHT is a key androgen involved in the miniaturization of hair follicles in AGA.
- Pharmacokinetics: Finasteride is well absorbed orally. It is metabolized primarily by the cytochrome P450 3A4 enzyme system in the liver. The elimination pathways are predominantly hepatic through biliary excretion, with less than 40% urinary excretion.
Minoxidil:
- Pharmacodynamics: Minoxidil is a potassium channel opener. The exact mechanism of action in hair growth is not fully elucidated, but it is thought to prolong the anagen phase of hair growth, increase blood flow to the hair follicle due to vasodilation, and stimulate the hair follicle to increase in size.
- Pharmacokinetics: Minoxidil is absorbed through the skin (topical application) and the gastrointestinal tract (oral formulations). It undergoes minimal systemic metabolism when applied topically. Systemic clearance occurs primarily via metabolism in the liver to inactive metabolites (minoxidil sulfate and glucuronide). Elimination is primarily renal.
Dosage
Standard Dosage
Adults:
- Topical Finasteride + Minoxidil: A solution containing 0.3% finasteride (3mg/mL) and 6% minoxidil (60mg/mL) is applied to the scalp once daily. A volume of 1mL should be used, preferably using a calibrated dropper.
- Oral Finasteride + Topical Minoxidil: Finasteride 1mg is taken orally once daily. Topical minoxidil, typically a 2% or 5% solution, is applied to the affected area twice daily.
Children:
Finasteride + Minoxidil is not generally recommended for children due to lack of robust clinical data on safety and efficacy in this population.
Special Cases:
- Elderly Patients: Dosage adjustments are usually not required, but closer monitoring for potential side effects is advised.
- Patients with Renal Impairment: For oral finasteride, no dosage adjustments are typically necessary. For topical minoxidil, systemic absorption is minimal, so dose adjustments are not generally recommended. If oral minoxidil is prescribed, careful monitoring of blood pressure is necessary and potential dose adjustments are required.
- Patients with Hepatic Dysfunction: For oral finasteride, use with caution. Monitor closely for side effects. For topical minoxidil, adjustments might be necessary in cases of severe impairment, but caution is advised.
- Patients with Comorbid Conditions: Dosage adjustment is determined case-by-case, depending on the specific conditions and their interaction with finasteride or minoxidil.
Clinical Use Cases
Finasteride + Minoxidil is not used in the clinical scenarios listed (Intubation, Surgical Procedures, Mechanical Ventilation, Intensive Care Unit (ICU) Use, Emergency Situations). It is indicated only for androgenetic alopecia.
Dosage Adjustments
Dosage adjustments are typically not needed for topical finasteride + minoxidil based on weight, renal function, or other factors. For oral finasteride, dose adjustments are generally not necessary for renal dysfunction, but caution is advised for severe hepatic impairment.
Side Effects
Common Side Effects (Finasteride):
- Decreased libido
- Erectile dysfunction
- Ejaculation disorders
- Gynecomastia
Common Side Effects (Minoxidil):
- Scalp irritation
- Itching
- Dryness
- Redness
- Unwanted hair growth in other areas
Rare but Serious Side Effects (Finasteride):
- Allergic reactions (rash, itching, swelling)
- Depression
- Changes in breast tissue (lumps, pain)
Rare but Serious Side Effects (Minoxidil):
- Dizziness
- Fainting
- Rapid heartbeat
- Swelling in the hands or feet
- Chest pain
Long-Term Effects: Long-term side effects of finasteride can include persistent sexual dysfunction even after discontinuation. Long-term effects of topical minoxidil are generally limited to local skin reactions.
Adverse Drug Reactions (ADR): Any severe or persistent side effects should be considered as a potential ADR and reported accordingly.
Contraindications
- Finasteride: Hypersensitivity to finasteride, use in women of childbearing potential or who are pregnant or breastfeeding.
- Minoxidil: Hypersensitivity to minoxidil, scalp inflammation or infections.
Drug Interactions
- Finasteride: No clinically significant drug interactions have been consistently reported.
- Minoxidil: Concurrent use with other topical medications or agents that irritate the scalp may increase the risk of local side effects. Systemic absorption of topical minoxidil is minimal; thus systemic drug-drug interactions are rare. Caution should be used with concomitant antihypertensives in case of oral formulations due to its potential for vasodilatory effects.
Pregnancy and Breastfeeding
- Finasteride: Contraindicated in pregnancy and breastfeeding (Pregnancy Category X). Finasteride can be absorbed through the skin; therefore, pregnant or breastfeeding women should avoid handling broken or crushed tablets.
- Minoxidil: Topical minoxidil’s safety during pregnancy and breastfeeding has not been definitively established. It is generally advised to avoid use unless deemed necessary by a physician.
Drug Profile Summary
- Mechanism of Action: Finasteride: 5-alpha reductase inhibitor. Minoxidil: Potassium channel opener.
- Side Effects: Finasteride: Decreased libido, erectile dysfunction, ejaculation disorders. Minoxidil: Scalp irritation, itching, unwanted hair growth.
- Contraindications: Finasteride: Hypersensitivity, use in women of childbearing potential, pregnancy, breastfeeding. Minoxidil: Hypersensitivity.
- Drug Interactions: Finasteride: None significant. Minoxidil: Potential additive effects with other antihypertensives if oral formulations are used.
- Pregnancy & Breastfeeding: Finasteride: Contraindicated. Minoxidil: Caution advised.
- Dosage: Varies depending on formulation. See section on Dosage.
- Monitoring Parameters: Monitor for efficacy (hair growth) and side effects, especially sexual side effects with finasteride, and scalp irritation with minoxidil. For oral formulations of minoxidil, blood pressure should be monitored.
Popular Combinations
The combination of finasteride and minoxidil is itself a popular and effective strategy for managing AGA.
Precautions
General precautions include assessing the patient’s medical history for any contraindications or potential drug interactions. Pregnant or breastfeeding women should not use finasteride and should use caution with topical minoxidil. Elderly patients might require closer monitoring for side effects. Advise patients to report any unusual or bothersome side effects.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Finasteride + Minoxidil?
A: For topical application, 1mL of a solution containing 0.3% finasteride and 6% minoxidil once daily is recommended. For oral finasteride plus topical minoxidil, finasteride 1mg is taken orally once daily, and topical minoxidil 2% or 5% is applied twice daily.
Q2: How long does it take to see results with Finasteride + Minoxidil?
A: Significant improvement is generally observed within 3 to 6 months, but optimal results can take up to a year or longer.
Q3: Are there any side effects associated with using both Finasteride and Minoxidil together?
A: The side effects of the combination are generally the same as those of the individual drugs used alone. These include sexual side effects (finasteride), scalp irritation (minoxidil), and others as described above.
Q4: Can women use Finasteride + Minoxidil?
A: Finasteride is contraindicated in women of childbearing potential, pregnant or breastfeeding women. Topical minoxidil can be used by women, but its safety during pregnancy and breastfeeding is not well-established.
Q5: What happens if I stop using Finasteride + Minoxidil?
A: The benefits achieved, such as hair regrowth, will gradually reverse, and hair loss will likely resume its previous course if treatment is discontinued.
Q6: Can Finasteride + Minoxidil completely cure hair loss?
A: No, it does not cure hair loss but effectively manages and slows its progression while stimulating regrowth. Continued use is generally needed to maintain the results.
Q7: Are there any dietary restrictions while using Finasteride + Minoxidil?
A: No specific dietary restrictions are associated with finasteride or topical minoxidil use.
Q8: Can I use other hair products while on Finasteride + Minoxidil?
A: Generally, yes, but avoid using other scalp irritants concomitantly with minoxidil.
Q9: Should patients with liver or kidney problems use Finasteride + Minoxidil?
A: Caution is advised, especially with oral finasteride in patients with severe hepatic impairment. Consult the Dosage section above for specific details.
Q10: How should I counsel my patients about starting Finasteride + Minoxidil?
A: Discuss the potential benefits, expected timeline for results, possible side effects, precautions, and the need for continuous use to maintain the treatment effect. Advise them to report any concerns or adverse effects promptly. Emphasize the importance of adherence to the prescribed regimen for optimal efficacy.
