Short answer: Minoxidil foam and minoxidil solution (spray) are the two principal topical vehicles for androgenetic alopecia, and the choice between them rests on scalp condition, application preference, and the concentration a prescriber wants. Clinical trials demonstrate efficacy for both foam and solution formulations, with foam showing comparable results to solution in female pattern hair loss. A compounding pharmacy can prepare a minoxidil solution, spray or gel at individualised strengths on a doctor’s prescription under Good Compounding Practice (GCP).
The evidence base for foam and solution vehicles
A multicentre, randomised, placebo-controlled, double-blind clinical trial of 5% minoxidil topical foam versus placebo in men with androgenetic alopecia demonstrated efficacy for the foam vehicle, establishing it as a validated delivery form for minoxidil (Olsen et al., Journal of the American Academy of Dermatology, 2007; PMID 17761356).
For female pattern hair loss, a phase III, randomised, investigator-blinded study compared once-daily 5% minoxidil foam against twice-daily 2% minoxidil solution, finding that the foam formulation produced comparable results to the solution — with the practical advantage of once-daily application (Blume-Peytavi et al., Journal of Drugs in Dermatology, 2016; PMID 27391640). An earlier randomised, single-blind trial of 5% minoxidil foam once daily versus 2% minoxidil solution twice daily in women with androgenetic alopecia reached a similar conclusion (Blume-Peytavi et al., Journal of the American Academy of Dermatology, 2011; PMID 21700360).
A separate phase III trial compared 5% minoxidil foam against vehicle in women with female pattern hair loss, confirming the foam’s efficacy over its own vehicle control (Bergfeld et al., Journal of Drugs in Dermatology, 2016; PMID 27391639).
Foam vs solution: the practical comparison
| Feature | Minoxidil foam | Minoxidil solution / spray |
|---|---|---|
| Application | Hands applied, massaged into scalp | Spray nozzle or dropper, applied to scalp |
| Frequency (in trials) | Once daily (5% foam) | Twice daily (2% solution) |
| Vehicle | Aerosol foam, no propylene glycol | Typically contains propylene glycol and alcohol |
| Scalp irritation | Less associated with contact dermatitis | Propylene glycol may cause irritation in sensitive patients |
| Hair length | Easier on short hair | Spray reaches scalp through longer hair |
The propylene glycol content of standard minoxidil solutions is a clinically relevant point. Propylene glycol is the solvent that keeps minoxidil in solution, but it is also a known cause of scalp irritation and allergic contact dermatitis in a subset of patients. The foam vehicle was developed partly to address this — it does not contain propylene glycol. For patients who experience irritation with the solution, a prescriber can specify a propylene-glycol-free vehicle through compounding, and the pharmacy can prepare a minoxidil preparation in a vehicle the prescriber selects.
When compounding adds value beyond commercial foam and solution
Commercial minoxidil products are manufactured at fixed strengths — typically 2% and 5%. A prescriber who wants a strength between these, or above 5%, or a combination of minoxidil with another active such as topical finasteride in a single preparation, turns to compounding. A compounded minoxidil preparation can be prepared as a liquid (solution or spray) or as a gel, at the strength the prescriber specifies, in a vehicle chosen for the individual patient’s scalp condition.
A study of minoxidil dose response in female pattern hair loss patients determined to be non-responders to 5% topical minoxidil explored higher concentrations, reflecting the clinical reality that some patients require doses outside the commercial range (McCoy et al., Journal of Biological Regulators and Homeostatic Agents, 2016; PMID 28078868). A network meta-analysis of monotherapy with 5-alpha reductase inhibitors and minoxidil for female pattern hair loss compared the relative effects of different treatment approaches, providing context for combination strategies (Gupta et al., Journal of Cosmetic Dermatology, 2024; PMID 37386777).
What a prescriber specifies for a compounded minoxidil preparation
- Active ingredient and concentration (e.g., minoxidil 3%, 5%, or higher)
- Dosage form: topical liquid (solution/spray) or gel
- Vehicle preference (e.g., propylene-glycol-free base where irritation is a concern)
- Additional actives, if combining (e.g., topical finasteride at a specified concentration)
- Named patient and prescriber details
Discussing a minoxidil preparation with Lynnity
Lynnity prepares compounded minoxidil as a non-sterile topical liquid (solution or spray) or gel for a named patient on a doctor’s prescription, under Good Compounding Practice (GCP). The prescriber specifies the concentration, vehicle and any additional actives; the pharmacy prepares to that specification. Where a patient in the same clinic requires a related hair-loss preparation — for example, a compounded minoxidil–finasteride combination in a single vehicle — the same prescription channel applies. Clinicians can include the formulation brief — vehicle preference, excipient exclusions, combination rationale — alongside the prescription, so the pharmacy can assess compatibility and stability before preparation.
Frequently asked questions
Is minoxidil foam more effective than minoxidil solution?
Clinical trials comparing 5% minoxidil foam once daily against 2% minoxidil solution twice daily in female pattern hair loss found comparable efficacy between the two vehicles. The foam’s advantage is practical — once-daily application and a propylene-glycol-free vehicle — rather than a difference in the active’s pharmacological effect.
Can a compounding pharmacy prepare minoxidil at a strength above 5%?
Yes. A compounding pharmacy prepares minoxidil at the concentration the prescriber specifies, which may be above the 5% commercial ceiling. The prescriber determines the clinical rationale for the higher concentration; the pharmacy prepares it on prescription under GCP.
What vehicle should be chosen for a patient who reacts to propylene glycol?
For patients who experience scalp irritation with propylene glycol-containing minoxidil solutions, a prescriber can specify a propylene-glycol-free vehicle on the compounding prescription. The pharmacy prepares the minoxidil in the alternative base specified.
Can minoxidil be combined with finasteride in a single compounded preparation?
Yes. A compounding pharmacy can prepare minoxidil and topical finasteride together in a single vehicle at the strengths the prescriber specifies. This is a prescription-only preparation made for one named patient, not a commercial product.
Reviewed by Vitthia Rama Murti, RPh (RPh 15632)
To discuss a patient-specific minoxidil preparation — whether a spray, solution or gel at an individualised strength — consult Lynnity’s compounding pharmacists, including Lead Pharmacist Vitthia Rama Murti, RPh (RPh 15632), at the compounding facility in MWE Commercial Park, Kepong, Kuala Lumpur.