Lets talk Formulations!
Propylene glycol is a common skincare ingredient used in pharmaceutical formulations and cosmetics, and is well tolerated. However, when it comes to hair loss, it is a different story. The rest of this article will summarise why some individuals cannot tolerate propylene glycol and the alternatives to consider.
Minoxidil is insoluble in water and is freely soluble at high concentrations of alcohol and propylene glycol. However, too much propylene glycol can cause a seborrheic dermatitis like reaction and affect compliance.
What to do if you have a propylene-glycol sensitivity
If propylene glycol is causing your scalp irritation, it is now possible to dissolve Minoxidil completely in solution using no propylene glycol. Propylene glycol-free formulations are personalised formulations. They are made by compounding pharmacists and is available for almost the same cost as full propylene glycol formulations.
Propylene Glycol-Free formulations generally contain more alcohol to help dissolve Minoxidil completely into solution. Recent revisions have seen lower concentrations of alcohol and the addition of other emulsifiers to preserve the skin barrier.
Foam formulations typically do not have propylene glycol. Some people also find foams are easier to apply when there is more hair present.
Gel formulations are a new option to consider. They are great for balding areas or areas that have very little hair. Gels can be massaged into the scalp without the product dripping everywhere. For Finasteride only gel, it is possible to formulate using a alcohol-free base. For Finasteride and Minoxidil gel, some alcohol is needed to completely dissolve minoxidil. This is important for minoxidil absorption and to create a smooth, elegant texture that doesn't feel grainy.
Hydro-alcoholic formulations contain water as well as alcohol (they are not alcohol-free). Hydro-alcoholic formulations are perfect for someone who wants the benefits of a fast drying formula but with less alcohol. The disadvantage with hydro-alcoholic formulations is that they have a shelf life of 30 days compared to alcoholic formulations.
Alcohol-free and Propylene Glycol-free solution is the most recent novel innovation. The absence of alcohol have sparked concerns that Minoxidil cannot be absorbed. If this theory holds true, all pharmaceutical creams and gels should also be formulated with alcohol, but they are not.
A 2023 clinical study by Udare et al showed that alcohol-free formulations proved to be just as effective as alcoholic minoxidil formulations and with significantly less side effects and is better tolerated. The study followed their patients for 12 months.
How do I know which formulation base is right for me?
Several factors must be considered when deciding which formulation base is right for you. These include ease of use, cost, travel, and storage.
These options can be discussed with your doctor or pharmacist if you have unique requirements.
Topical solutions are the most popular because they are cost effective, easy to travel with and easy to use.
Author: Helen Huynh (B. Pharm) MPS
References:
- Udare, S et al (2023). "Low-Alcohol or Alcohol-Free Minoxidil Formulation for the Management of Androgenic Alopecia: an Indian Perspective." International Journal of Trichology. 15(1): p13-17, Jan-Feb 2023.
- Olsen, E et al. (2002). "A randomized clinical trial of 5% topical minoxidil versus 2% topical minoxidil and placebo in the treatment of androgenetic alopecia in men." Journal of the American Academy of Dermatology, 47(3), 377 385.
- Roberts, J et al (2014). "Response to Topical Minoxidil in Female Androgenic Alopecia." Journal of Dermatologic Therapy. Jul-Aug;27(4):252-4
