Research shows that micro-needling can increase hair counts by up to 15% and even as much as 400% when combined with drug therapies such as 5% Minoxidil. The devices used for micro-needling include derma roller, micro-needle stamps and automated stamping devices with needle lengths ranging from 0.25mm to 2.5mm.
The big question for most people is: what needle length is best for stimulating hair growth?
Interestingly, research shows that the needle length that is required to stimulate hair growth depends on a few factors:
- How often you intend to micro-needle,
- If you are combining micro-needling with other modalities, such as Minoxidil and
- The treatment endpoint.
Shorter needle lengths between 0.25mm and 0.5mm will assist with the absorption of topicals into the scalp tissue. The needles need to be longer to reach the dermis where the hair bulb reside. The best results are seen with derma rollers containing needle lengths of 1.5mm or more. When using an automated stamping pen, needle lengths can be reduced to 0.8mm to 1.0mm.
The difference in needle length considers the angle at which the needle penetrates the skin surface. For derma rollers, it is usually rolled at a 45% degree angle, so the needle length needs to be longer. For automated pens, the penetration occurs at almost a 90-degree angle; hence, a shorter needle is sufficient.
What is microneedling and how does microneedling work?
Microneedling is a simulation method that contains hundreds of tiny medical-grade needles. It is believed that micro needling to balding scalp stimulates hair growth by:
- Stimulation of growth factors to the area,
- The growth factors (GF) promote the formation of new blood vessels over time and
- GF and blood vessels (carrying oxygen and nutrients) encourage follicle growth.
The scalp does not have not be completely bald to see these benefits. Micro-needling also enhances the absorption of topical solutions. For this reason, a non-alcoholic Minoxidil formulation is less likely to cause irritation and burning compared to traditional foams and solutions. Traditional Minoxidil formulations contain up to 70% alcohol and is best avoided on skin with micro tears.
Evidence for micro-needling for the treatment of hair loss in women
Several studies have shown that the benefits of micro-needling are enhanced when combined with topical Minoxidil in both men and women. One notable study in 2018 involving 40 women showed the clinical efficacy rate for micro-needling combined with 2% topical minoxidil was 85% compared to 45% when Minoxidil is used as a standalone therapy. This represents an 88.8% increase in hair counts when dual therapy is deployed.
Other studies demonstrated that 5% topical Minoxidil combined with micro-needling showed an even higher percentage increase in hair growth over twelve weeks.
Who will benefit from micro-needling?
Micro-needling has shown to increase hair counts even when it is used as standalone modality. The disadvantage of using micro-needling by itself is that results can be slow, especially if you have already lost most of your hair. That said, we believe micro-needling can be effective in the following settings:
- If you have mild hair loss and prefer non pharmaceutical interventions,
- If you have restored your hair and want to maintain the growth that you have without using pharmaceutical drugs, and
- If you want fast results - studies show micro-needling can safely be used in combination with either Minoxidil or Finasteride. Combining these modalities will only accelerate your results.
How to combine topical Minoxidil and micro-needling for hair growth
Disclaimer: the following advice is to be used a guide only.
Pick a day you have time to perform the micro-needling session. Micro-needling does not have to be performed daily to see benefits because you also want to give the skin time to heal and repair.
Ensure the area you intend to perform micro-needling is clean and the device is also clean and sterilised. The needles should also be medical-grade needles, not hard plastic. Roll the derma roller over the area until there is redness (erythema). Some reports suggest the session endpoint should result in pin-point bleeding, but again, numerous research show this is not necessary.
Apply your topical Minoxidil as usual. You should repeat this process weekly for at least twelve weeks. Micro-needling creates minor puncture wounds to the scalp tissue and, therefore, also enhances the absorption of topical solutions. For this reason, a non-alcoholic Minoxidil formulation is preferred.
What if you didn't want to do microneedling at home?Research shows it is possible to achieve similar results when micro-needling sessions are done in the clinic every four weeks. The session endpoints are more enhanced, resulting in pin-point bleeding. The degree of wounding is more profound compared to inducing erythema and micro-wounds (which is what you are doing at home). Session endpoints that result in pin-point bleeding should be performed in the clinic due to the risk of infections.
Author: Dan Atkinson B. Pharm
- Lingling, J et al (2022). Effects of microneedling and 5% topical Minoxidil solution combination therapy in androgenic alopecia. Journal of Cosmetic Dermatology. July 21, 2022. Accessed October 16, 2023.
- Stong, C (2022). Microneedling and topical Minoxidil Combination Effective for Female Pattern Hair loss. Dermatology Advisor. December 1, 2022.
- Roberts, J et al (2014). "Response to Topical Minoxidil in Female Androgenic Alopecia." Journal of Dermatologic Therapy. Jul-Aug;27(4):252-4