Frequently Asked Questions

A 40 ml antioxidant gel-serum built around methylene blue at cosmetic concentration, supported by eight further actives — niacinamide, ectoin, tremella, N-acetyl glucosamine, centella asiatica, green tea, beta-glucan, and squalane with panthenol. Fragrance-free, vegan, made in London. Full breakdown in our ingredient glossary.

It means the formula is built around ingredients that interact with cellular energy metabolism rather than working only on the skin surface. We explain the category in full on our mitochondrial skincare page.

There is mechanistic evidence and early laboratory work, including a 2017 study in cultured human fibroblasts and a reconstructed skin model. There is not yet a body of large controlled human trials for topical cosmetic use. We think the ingredient is genuinely interesting and we are not going to overstate it. The full picture, including limitations, is on our methylene blue guide.

No. At cosmetic concentration methylene blue does not tint skin and does not transfer to fabric once absorbed.

40 ml. At two to three drops once daily, a bottle typically lasts around two months; twice daily use roughly halves that.

After cleansing, before moisturiser. Two to three drops on clean, slightly damp skin. Full guidance on our how to use page.

Either, or both. It is not a photosensitiser in the way retinoids are. Consistency matters more than timing.

Yes, but alternate rather than stack. Use it on nights you are not applying a prescription retinoid or a strong exfoliating acid, or use it in the morning instead.

Hydration and comfort within the first week. Surface smoothness and tone at two to four weeks. Texture and firmness should be judged at six to twelve weeks of consistent use. Take a photo on day one in consistent light — memory is unreliable for gradual change.

It is designed to be — fragrance-free, with ectoin, centella and panthenol included for tolerance. Patch test on the inner forearm for 24 hours before facial use, as with any new product.

Check with your midwife or GP before introducing any new active during pregnancy or breastfeeding.

If you take serotonergic medication — SSRIs, SNRIs or MAOIs — or have G6PD deficiency, speak to your GP or pharmacist first. These cautions relate to systemic methylene blue rather than topical cosmetic use, but it is a conversation worth having.

We ship across the United Kingdom. Detail, timings and costs are on our shipping policy.

Timings and carrier detail are set out on our shipping policy page. You will receive tracking by email once your order is dispatched.

Yes — see our returns and refund policy for the window and the process.

Accepted methods are listed on our payment information page.

Formulated and manufactured in London, under UK cosmetic regulations — which means a Cosmetic Product Safety Report on file, a named Responsible Person and full batch traceability. More on our about page.

Yes to both. No animal-derived ingredients and no animal testing, which is prohibited for cosmetics sold in the UK in any case.

Yes — the complete INCI list is on the product page and printed on the carton, and every active is explained in our ingredient glossary.

Email info@skintervene.com or use our contact form.