- Introduction: Why Dosage Precision Matters
- Quick-Reference Master Dosage Table
- FDA-Approved Hair Loss Compounds
- CB-03-01 (Clascoterone / Breezula)
- RU58841
- WAY-316606
- Setipiprant
- Fevipiprant
- OTC & Natural Compounds Dosage
- Combination Therapy Dosage Protocols
- Dose-Response Relationships
- Factors Affecting Dosage Selection
- Dose-Dependent Safety Considerations
- Special Populations & Adjustments
- Frequently Asked Questions
- Conclusion & Key Takeaways
1. Introduction: Why Dosage Precision Matters
Hair loss treatment is one of the most dosage-sensitive therapeutic areas in dermatology. Too little active compound yields no visible results; too much risks side effects ranging from scalp irritation to systemic hormonal disruption. The challenge is compounded by the fact that hair loss compounds span an extraordinarily wide range — from FDA-approved drugs with decades of pharmacokinetic data to research chemicals with only preclinical dosing information.
This guide consolidates the dosing information for 14+ hair loss compounds across three regulatory tiers:
- FDA-approved drugs (Minoxidil, Finasteride, Dutasteride, Spironolactone, Ketoconazole) with established clinical dosing
- Clinical-stage investigational compounds (CB-03-01/clascoterone, Setipiprant, Fevipiprant) with Phase 2/3 trial dosing protocols
- Research chemicals (RU58841, WAY-316606) with preclinical and community-based dosing protocols
The dosages listed for investigational and research compounds (RU58841, WAY-316606, Setipiprant, Fevipiprant) are derived from clinical trial protocols, preclinical studies, or community use reports — not from FDA-approved labeling. These compounds are not approved for hair loss treatment and are intended for laboratory research purposes only.
2. Quick-Reference Master Dosage Table
The following table provides a bird's-eye view of all compounds covered in this guide. Detailed dosing cards for each compound follow in subsequent sections.
| Compound | Route | Standard Dose | Frequency | Status |
|---|---|---|---|---|
| Minoxidil (men) | 5% solution, 1 mL | Twice daily | ||
| Minoxidil (women) | 2% solution, 1 mL | Twice daily | ||
| Oral Minoxidil (men) | 2.5–5 mg | Once daily | ||
| Oral Minoxidil (women) | 0.25–1 mg | Once daily | ||
| Finasteride | 1 mg | Once daily | ||
| Dutasteride | 0.5 mg | Once daily | ||
| Spironolactone (women) | 25–200 mg | Once daily | ||
| Ketoconazole shampoo | 2%, 3–5 min contact | 2–3x weekly | ||
| CB-03-01 (Clascoterone) | 5% solution, 1.5 mL | Twice daily | ||
| RU58841 | 5% (50 mg/mL), 1 mL | Once daily | ||
| WAY-316606 | 2 μM (in vitro) | Single incubation | ||
| Setipiprant | 1000 mg (2×500 mg) | Twice daily | ||
| Fevipiprant | 150 mg or 450 mg | Once daily | ||
| Latanoprost | 50–500 μg/mL | Once daily |
3. FDA-Approved Hair Loss Compounds
💊 FDA-Approved for Androgenetic Alopecia
FDA-Approved1 mL applied to dry scalp
or 5% foam: once daily
Once daily (oral)
12 months for full effect
Vehicle: Solution contains propylene glycol (may cause irritation); foam is propylene glycol-free. Application: Apply to dry scalp, spread evenly, allow to dry before styling. Note: Treatment must continue indefinitely — discontinuation reverses all gains within 3–4 months. Initial shedding may occur in first 2–8 weeks (normal sign of follicle re-entry into anagen).
DHT reduction ~70%
6–12 months: visible regrowth
Postmenopausal: off-label use
Baseline + annual monitoring
Side effects (≤2%): Decreased libido, erectile dysfunction, gynecomastia. Usually reversible upon discontinuation. Duration: Must be taken indefinitely; stopping reverses effects within 12 months. The 5 mg dose (Proscar) is used for BPH and is sometimes quartered off-label for hair loss cost savings.
DHT reduction >90%
vs. Finasteride: More potent DHT suppression, longer half-life, dual isoenzyme inhibition. Approved for BPH at 0.5 mg; widely used off-label for AGA. Approved for male AGA in Japan and South Korea. Contraindicated in pregnant women. Blood donation prohibited for 6 months after last dose.
Max: 200 mg/day
Mechanism: Mineralocorticoid receptor antagonist with antiandrogenic properties. Reduces testosterone and DHT production. Key side effects: Hyperkalemia (especially with renal impairment), hypotension, menstrual irregularities. Contraception: Mandatory in women of childbearing potential due to risk of feminization of male fetus.
1% (OTC, Nizoral A-D)
Mechanism for hair: Anti-androgenic (reduces follicular DHT 12–16%), anti-inflammatory (reduces IL-1α), anti-fungal (controls Malassezia). Not a standalone treatment — used as adjunct to minoxidil and finasteride. Important: Apply minoxidil only after scalp is completely dry post-shampoo. Do not use within 24 hours of microneedling.
4. CB-03-01 (Clascoterone / Breezula)
CB-03-01 (clascoterone) is the most advanced topical anti-androgen for androgenetic alopecia, currently in Phase 3 clinical trials. Unlike oral 5α-reductase inhibitors (finasteride, dutasteride) that reduce systemic DHT, clascoterone blocks androgen receptors locally at the hair follicle, avoiding systemic hormonal side effects.
| Trial Phase | Concentration | Volume per Application | Frequency | Daily Dose | Duration |
|---|---|---|---|---|---|
| Phase 3 (SCALP1/SCALP2) | 5% solution | 1.5 mL | Twice daily | 150 mg | 12 months |
| Phase 2 (optimal) | 7.5% solution | 1.5 mL | Twice daily | 225 mg | 12 months |
| Phase 2 (mid-dose) | 5% solution | 1.5 mL | Twice daily | 150 mg | 12 months |
| Phase 2 (low-dose) | 2.5% solution | 1.5 mL | Twice daily | 75 mg | 12 months |
| Winlevi (acne, FDA-approved) | 1% cream | Thin layer | Twice daily | ~20–40 mg | 12 weeks |
Phase 2 data showed that the 7.5% concentration applied twice daily produced the most significant hair growth improvements. However, the Phase 3 trials selected the 5% concentration at 1.5 mL twice daily, likely balancing efficacy with safety/scalp tolerability. If approved, Breezula would be the first new FDA-approved hair loss drug in nearly 30 years and the first topical anti-androgen for AGA.
5. RU58841
RU58841 is the most widely used research chemical for topical anti-androgen therapy. Developed by Roussel Uclaf in the 1990s, it was never submitted for FDA approval but has accumulated extensive community use data. Its key advantage over clascoterone is significantly lower cost and broader availability from research chemical suppliers.
| Protocol | Concentration | Volume | Frequency | Daily Dose | Vehicle |
|---|---|---|---|---|---|
| Standard (community) | 5% (50 mg/mL) | 1 mL | Once daily | 50 mg | 70% ethanol / 30% PG |
| Conservative start | 2.5% (25 mg/mL) | 1 mL | Once daily | 25 mg | 70% ethanol / 30% PG |
| Split dosing (short t½) | 5% (50 mg/mL) | 0.5 mL | Twice daily | 50 mg | 70% ethanol / 30% PG |
| High dose (advanced) | 7.5% (75 mg/mL) | 1 mL | Once daily | 75 mg | 70% ethanol / 30% PG |
| Preclinical (macaque) | 5% (50 mg/mL) | ~1 mL | Once daily | ~50 mg | Hydroalcoholic vehicle |
6 months: fair assessment
12 months: full evaluation
RU58841 has an extremely short systemic half-life (~1 hour) due to rapid hydrolysis to inactive metabolites. This is an advantage for minimizing systemic side effects, but it means that once-daily application may not maintain continuous androgen receptor blockade. The split-dosing protocol (0.5 mL BID of 5% solution) may provide more sustained receptor occupancy, though most users apply once daily for convenience.
6. WAY-316606
WAY-316606 represents a completely novel mechanism for hair loss: instead of blocking DHT or PGD2, it activates the Wnt/β-catenin signaling pathway by inhibiting SFRP-1 (Secreted Frizzled-Related Protein 1), a natural Wnt inhibitor. This promotes hair follicle regeneration and prolongs the anagen (growth) phase. No human clinical dosing exists; all data is from ex vivo human hair follicle organ culture.
| Parameter | Value | Notes |
|---|---|---|
| Working concentration | 2 μM (0.896 μg/mL) | In serum-free Williams' E media |
| Stock solution | 10 mM in DMSO | 10 mg in 2,229.8 μL DMSO |
| Dilution | 4 μL stock in 19,996 μL media | Final DMSO: 0.02% |
| qRT-PCR incubation | 24 hours | AXIN2 mRNA upregulation |
| β-catenin activity | 48 hours | Nuclear β-catenin immunofluorescence |
| Hair cycle analysis | Up to 6 days | Anagen prolongation assessed |
| SFRP-1 inhibition at 2 μM | ~40% | Highly selective vs. SFRP2 (~5%) and SFRP5 (~2%) |
In solvent: -80°C, 2 years; -20°C, 1 year
The 2 μM ex vivo concentration cannot be directly translated to a topical human dose. In clinical development, formulation chemists would need to determine a topical concentration (likely in the 0.1–1% range) and application protocol that achieves therapeutic SFRP-1 inhibition at the dermal papilla level while maintaining safety. The lack of any IND filing for WAY-316606 in hair loss suggests significant translational development remains.
7. Setipiprant
Setipiprant was the first CRTh2 antagonist to reach clinical testing for androgenetic alopecia, targeting the PGD2-CRTh2 pathway. After its Phase 2a trial (NCT02781311) failed to demonstrate efficacy, development for hair loss was discontinued. However, its dosing protocol remains the only clinical dosing reference for PGD2-pathway blockade in AGA.
Active comparator: Finasteride 1 mg once daily (n=12, arm removed by protocol amendment). Common AEs: Nasopharyngitis, headache, upper respiratory tract infection. No serious treatment-emergent AEs in setipiprant group.
8. Fevipiprant
Fevipiprant is a more potent CRTh2 antagonist than setipiprant, developed by Novartis for asthma (not hair loss). Despite completing extensive Phase 3 trials (ZEAL-1, ZEAL-2, LUSTER-1, LUSTER-2), it failed to meet efficacy endpoints and was discontinued. No clinical trials for hair loss have been conducted.
| Dose | Frequency | Indication | Key Trial | Result |
|---|---|---|---|---|
| 150 mg | Once daily | Moderate-to-severe asthma | ZEAL-1, ZEAL-2, LUSTER-1, LUSTER-2 | Failed primary endpoints |
| 450 mg | Once daily | Moderate-to-severe asthma | ZEAL-1, ZEAL-2, LUSTER-1, LUSTER-2 | Failed primary endpoints |
| 150 mg or 450 mg | Once daily | Long-term safety (52 + 104 weeks) | NCT03052517 (n=2,538) | Safety established; efficacy not met |
| 150 mg or 450 mg | Once daily | Steroid-sparing in severe asthma | NCT03629249 (n=604) | Failed; discontinued |
9. OTC & Natural Compounds Dosage
🌿 Over-the-Counter & Natural Compounds
OTC / Natural10. Combination Therapy Dosage Protocols
Combination therapy is the standard of care in modern hair loss treatment. The following protocols represent evidence-based combinations with specific dosing for each component:
| Protocol | Component 1 | Component 2 | Component 3 (Optional) | Indication |
|---|---|---|---|---|
| Gold Standard (Men) | Finasteride 1 mg PO QD | Minoxidil 5% topical 1 mL BID | Ketoconazole 2% shampoo 2–3×/week | Male AGA (Norwood II–V) |
| Gold Standard (Women) | Spironolactone 50–100 mg PO QD | Minoxidil 2% topical 1 mL BID | Ketoconazole 2% shampoo 2–3×/week | Female AGA (Ludwig I–III) |
| Advanced Anti-Androgen | Dutasteride 0.5 mg PO QD | RU58841 5% topical 1 mL QD | Minoxidil 5% topical 1 mL BID | Refractory male AGA |
| Topical-Only Stack | Minoxidil 5% topical 1 mL BID | RU58841 5% topical 1 mL QD | Ketoconazole 2% shampoo 2–3×/week | Men avoiding oral meds |
| Clascoterone + Minoxidil | CB-03-01 5% topical 1.5 mL BID | Minoxidil 5% topical 1 mL BID | — | If Breezula approved (2026+) |
| Oral Minoxidil + Finasteride | Oral minoxidil 2.5–5 mg PO QD | Finasteride 1 mg PO QD | — | Convenience preference |
| Triple Research Stack | Finasteride 1 mg PO QD | RU58841 5% topical 1 mL QD | Minoxidil 5% + Tretinoin 0.025% QD | Advanced research protocol |
- Stagger topical applications — apply different topicals at different times (e.g., minoxidil AM, RU58841 PM) to avoid vehicle interference
- Allow 4 hours between topical applications to ensure complete absorption of the first compound
- Ketoconazole on non-minoxidil days or at least 4 hours apart — shampoo removes sebum that may aid minoxidil absorption
- Start one compound at a time — introduce new treatments 4–6 weeks apart to identify cause of any side effects
- Do not exceed maximum doses — more is not better and increases side effect risk without proportional benefit
11. Dose-Response Relationships
Understanding the dose-response curve for each compound is critical for optimizing therapy. Below is a summary of key dose-response data from clinical and preclinical studies:
| Compound | Sub-therapeutic | Standard | High Dose | Dose-Limiting Factor |
|---|---|---|---|---|
| Minoxidil (topical) | <2% — minimal effect | 5% BID — optimal | 10%+ — hypertrichosis risk | Scalp irritation, facial hair |
| Finasteride | 0.2 mg — partial DHT suppression | 1 mg — ~70% DHT reduction | 5 mg — no additional hair benefit | Sexual side effects (plateau at 1 mg) |
| Dutasteride | 0.1 mg — partial effect | 0.5 mg — >90% DHT reduction | 2.5 mg — used in some studies | Long half-life; cumulative exposure |
| CB-03-01 | 2.5% BID — modest response | 5% BID — Phase 3 dose | 7.5% BID — best Phase 2 efficacy | Scalp tolerability, cost |
| RU58841 | 2.5% QD — conservative | 5% QD — standard | 7.5%+ QD — no proven benefit | Unknown systemic absorption |
| Setipiprant | — | 1000 mg BID — failed | — | Efficacy ceiling reached |
| Ketoconazole | 1% — mild benefit | 2% — optimal | >2% — no added benefit | Scalp dryness, irritation |
| Latanoprost | 50 μg/mL — minimal | 500 μg/mL — effective | — | Cost, availability of high conc. |
12. Factors Affecting Dosage Selection
Dosage is not one-size-fits-all. The following factors should guide individualized dosing decisions:
13. Dose-Dependent Safety Considerations
| Compound | Low-Dose Risk | Standard-Dose Risk | High-Dose Risk | Monitoring Required |
|---|---|---|---|---|
| Minoxidil (topical) | Minimal | Irritant dermatitis, hypertrichosis | Systemic absorption, tachycardia | Blood pressure (if symptomatic) |
| Finasteride | Very low | Sexual dysfunction (~2%), mood changes | No additional benefit; cumulative risk | PSA baseline + annual |
| Dutasteride | Low | Sexual dysfunction (~3–4%) | Hepatotoxicity (rare) | PSA, liver enzymes |
| Spironolactone | Low at 25 mg | Hyperkalemia, hypotension | Severe hyperkalemia, arrhythmia | K+, renal function, BP |
| CB-03-01 | Minimal (local) | Scalp irritation, pruritus | Unknown (limited data above 7.5%) | Clinical trial monitoring |
| RU58841 | Unknown | Scalp irritation, unknown systemic effects | Unknown — no clinical safety data | None established |
| Setipiprant | — | Headache, nasopharyngitis (25.9%) | — | Liver function (phase 2) |
| Fevipiprant | — | Headache, GI symptoms (<10%) | Similar AE profile at 450 mg | Liver function (Phase 3) |
| Ketoconazole | Minimal | Scalp dryness, irritation | Contact dermatitis | Liver function (oral only) |
14. Special Populations & Adjustments
Women of Childbearing Potential
- Finasteride/Dutasteride: Absolutely contraindicated. Even crushed tablet dust can cause fetal abnormalities.
- Spironolactone: Effective but requires reliable contraception (feminization of male fetus).
- Minoxidil: 2% solution preferred; 5% foam once daily acceptable. Oral minoxidil 0.25–1 mg off-label.
- RU58841/CB-03-01: No pregnancy safety data. Avoid.
Postmenopausal Women
- Finasteride 1 mg may be used off-label (no teratogenic risk).
- Spironolactone remains effective but lower hyperkalemia threshold with age.
- Lower-dose minoxidil (2%) with careful BP monitoring.
Elderly Patients (>65)
- Start at lower doses; titrate slowly.
- Spironolactone: start 25 mg, max 50–100 mg (renal function dependent).
- Oral minoxidil: increased orthostatic hypotension risk; use with caution.
- Dutasteride: prolonged half-life may be further extended in hepatic impairment.
Patients with Hepatic Impairment
- Finasteride: no dose adjustment needed for mild-moderate; avoid in severe.
- Dutasteride: avoid in severe hepatic impairment.
- Spironolactone: use with caution; monitor closely.
- Oral ketoconazole: contraindicated (hepatotoxicity risk).
15. Frequently Asked Questions
The standard community dosage of RU58841 is a 5% (50 mg/mL) topical solution applied at 1 mL once daily to affected areas of the scalp. The solution is typically prepared in a vehicle of 70% ethanol and 30% propylene glycol. A conservative starting dose is 2.5% (25 mg/mL) at 1 mL once daily. Some users apply 0.5 mL twice daily instead of 1 mL once daily, given RU58841's short systemic half-life of approximately 1 hour. Results typically require 3–6 months of consistent daily application.
In the ongoing Phase 3 clinical trials (SCALP1 and SCALP2), CB-03-01 is administered as a 5% topical solution applied at 1.5 mL twice daily to the balding areas of the scalp (vertex and temples), for a total daily dose of 150 mg. Phase 2 trials tested 2.5%, 5%, and 7.5% concentrations, with the 7.5% solution applied twice daily yielding the most significant hair growth improvements. The FDA-approved acne formulation (Winlevi) contains 1% clascoterone cream, which is not intended for scalp hair loss.
In the Phase 2a clinical trial (NCT02781311), Setipiprant was administered orally at 1000 mg (two 500 mg tablets) twice daily (BID) at 12-hour intervals for 24 weeks, resulting in a total daily dose of 2000 mg. The trial enrolled 169 men aged 18–49 with androgenetic alopecia. While the compound was safe and well-tolerated, it failed to meet its primary efficacy endpoints for hair regrowth compared to placebo.
In the landmark Hawkshaw et al. (2018) ex vivo study, WAY-316606 was used at a 2 μM working concentration in serum-free hair follicle media. A 10 mM stock solution was prepared in DMSO and subsequently diluted (4 μL of 10 mM stock in 19,996 μL of media). Hair follicles were incubated for 24 hours (qRT-PCR), 48 hours (β-catenin activity), and up to 6 days (hair cycle analysis). No human clinical dosing has been established.
For male pattern hair loss, the standard dosage is 5% minoxidil solution or foam applied at 1 mL (or half a capful of foam) to the scalp twice daily. For female pattern hair loss, the standard is 2% minoxidil solution at 1 mL twice daily, or 5% foam applied once daily. Low-dose oral minoxidil (2.5–5 mg daily for men, 0.25–1 mg daily for women) is also used off-label. Treatment must continue indefinitely to maintain results.
Finasteride is dosed at 1 mg orally once daily for male androgenetic alopecia, with evaluation after 6–12 months. Dutasteride is dosed at 0.5 mg orally once daily (off-label for hair loss). Dutasteride is more potent because it inhibits both Type 1 and Type 2 5α-reductase, reducing DHT by over 90% versus Finasteride's approximately 70%. Dutasteride also has a much longer half-life (~5 weeks vs 6–8 hours for Finasteride). Both are contraindicated in pregnant women.
Yes, combination therapy is common and often more effective than monotherapy. Common combinations include: Minoxidil 5% BID + Finasteride 1mg daily (growth stimulation + DHT reduction), RU58841 5% topical + Finasteride 1mg oral (local + systemic anti-androgen), and Ketoconazole 2% shampoo 2–3x/week + Minoxidil + Finasteride (triple therapy). When combining, apply topical compounds at different times of day to avoid absorption interference. Always consult a physician before combining treatments.
Fevipiprant (QAW039) was tested in Phase III asthma trials at two oral doses: 150 mg once daily and 450 mg once daily. The safety study (NCT03052517) included a 52-week double-blind period followed by an optional 104-week extension. No clinical trials have been conducted for Fevipiprant in hair loss. The compound was discontinued by Novartis after failing to meet efficacy endpoints in asthma Phase III trials.
16. Conclusion & Key Takeaways
This comprehensive dosing reference covers the full spectrum of hair loss compounds — from FDA-approved mainstays to cutting-edge research chemicals. The following key takeaways summarize the essential dosing principles:
| Key Takeaway | Details |
|---|---|
| 1. Start low, titrate up | Begin with standard doses and evaluate at 3–6 months before increasing. Most compounds show a plateau effect beyond standard doses. |
| 2. Combination > monotherapy | The gold standard is multi-target therapy (e.g., finasteride + minoxidil + ketoconazole). Different mechanisms provide synergistic benefits. |
| 3. Consistency is critical | All hair loss treatments require indefinite use. Discontinuation reverses gains within 3–12 months depending on the compound. |
| 4. CB-03-01 is the future | If approved, 5% clascoterone BID would be the first new AGA drug in 30 years and the first topical anti-androgen with Phase 3 data. |
| 5. RU58841 remains the research standard | 5% (50 mg/mL) once daily is the most widely used community protocol, but no clinical safety data exists. |
| 6. Setipiprant & Fevipiprant are dead ends | CRTh2 antagonism alone is insufficient for AGA. Both compounds failed their respective clinical endpoints. |
| 7. WAY-316606 is promising but early | 2 μM ex vivo data is exciting but no human dosing exists. Significant translational development is needed. |
- Minoxidil: 5% BID (men), 2% BID (women) — 1 mL per application
- Finasteride: 1 mg PO QD
- Dutasteride: 0.5 mg PO QD
- Spironolactone: 25–200 mg PO QD (women only)
- Ketoconazole: 2% shampoo, 2–3×/week, 3–5 min contact
- CB-03-01: 5% solution, 1.5 mL BID (Phase 3)
- RU58841: 5% (50 mg/mL), 1 mL QD (research only)
- WAY-316606: 2 μM ex vivo (preclinical only)
- Setipiprant: 1000 mg BID PO (Phase 2a, failed)
- Fevipiprant: 150 or 450 mg QD PO (Phase 3 asthma, no hair loss data)
The compounds and dosages discussed in this article are presented for informational and educational purposes only. FDA-approved drugs (Minoxidil, Finasteride, Dutasteride, Spironolactone, Ketoconazole) should only be used under physician supervision. Investigational compounds (CB-03-01, RU58841, WAY-316606, Setipiprant, Fevipiprant) are unapproved research chemicals not evaluated by the FDA for hair loss treatment. RU58841, WAY-316606, Setipiprant, and Fevipiprant are intended solely for in vitro laboratory research and analytical purposes. This article does not constitute medical advice, treatment recommendation, or endorsement of any compound for human use. Always consult a qualified healthcare provider before starting any hair loss treatment.
Need High-Purity Hair Loss Research Compounds?
NutraBiotech provides CB-03-01, RU58841, WAY-316606, Setipiprant, Fevipiprant, and other research-grade hair loss compounds with full COA documentation, HPLC purity verification (≥98%), and batch-specific testing. Available in gram to kilogram quantities for laboratory research.
Request a Quote