Scalp micropigmentation (SMP)

Key takeaways

• It is camouflage, not treatment. Pigment is placed between follicles in a stippling pattern that resembles closely cut hair, and under a dermatoscope it shows as even grey-black dots slightly larger than real follicle openings (Nguyen 2022). It does not stop loss, so people with ongoing pattern loss still need medical treatment such as finasteride.
• Evidence is thin. A 2025 series of 10 patients (6 pattern loss, 4 scarring) reported high satisfaction (2.7 out of 3) and a visual density score falling from 8.7 to 7.7 over 6 months, with more fading in scarring alopecia and no control group (Liu 2025). No randomized trials were found.
• Density can help decide between SMP and a transplant in women. In a retrospective study of 40 women (23 transplant, 17 SMP), SMP suited those with hair density of about 104.6 hairs per cm2 or more, and transplant those at about 96 or below (Park 2024). This is one centre's analysis.
• Who does it matters. Among 120 patients seeking correction of poor SMP in Korea, 89.2% had been treated at a beauty salon doing permanent makeup. Most were fixed by laser removal, repeat SMP or hair transplant, but correction is hard (Park 2025).
• It can be removed, but not always easily. A 1064 nm picosecond laser cleared unwanted SMP in 1 to 3 sessions in 4 patients (Wu 2020).
• It is also used to hide scars and transplant donor marks (Rassman 2015).

What it is

A practitioner uses a tattoo-style machine with fine needles to deposit pigment into the upper skin layer in a dot pattern. Technique papers recommend several sessions, building pigment density gradually, and staying shallow to avoid bleeding (Park 2022). Whether pigment fades blue or grey over years is a common worry; long-term controlled data were not found.

What the studies show

The published literature is small case series, retrospective studies and narrative reviews, and several authors are practising SMP clinicians. Gradual fading over 6 months is the only measured long-term finding.

Side effects and safety

Risks follow those of any tattoo: infection, allergic or granulomatous reactions to pigment, uneven or poorly colour-matched dots, blurring, and difficulty removing. US tattoo ink oversight lacks enforceable composition limits, whereas the EU restricts certain chemicals. Tattooing is mostly regulated at state or local level in the US as hygiene and licensing, not as a medical device (Rassman 2015).

Bottom line

SMP suits a shaved or very short style, or hiding scars and thin patches, once any underlying scalp disease is quiet. Check a practitioner's before-and-after photos from 1 and 3 or more years ago, ask about pigment brand, hygiene and the removal plan, and keep treating the underlying hair loss. Discuss with a doctor.