All Ingredients
35

Methylisothiazolinone

Moderate

Quick verdict

High concern

Methylisothiazolinone skin safety dashboard

Methylisothiazolinone scores 35/100 across 1 product analyses. The most important acne and irritation checks are summarized first.

Comedogenic rating

5/5

High pore-clogging risk signal for acne-prone skin.

Fungal acne concern

Review

Review the full formula before using on Malassezia-prone skin.

Pregnancy concern

Review

Ask a clinician before using during pregnancy or nursing.

Skin types to avoid

Acne-prone, Oily, Sensitive

Based on pore-clogging and irritation risk signals.

What is Methylisothiazolinone and why is it used?

We're still generating a detailed description for Methylisothiazolinone. Check back shortly - or scan a product containing this ingredient to speed things up.

Will Methylisothiazolinone clog my pores? (Comedogenic Rating)

Comedogenic Risk: 5/5

Methylisothiazolinone has an estimated comedogenic risk of 5/5 based on GlowLens ingredient scoring across 1 product analyses. A higher number signals a stronger pore-clogging tendency for acne-prone skin. This is informational, not medical advice.

Known Side Effects and Allergies: how concerning is Methylisothiazolinone?

Moderate

Methylisothiazolinone currently scores 35/100, which places it in a moderate-concern band overall. The main practical consideration is skin irritation, sensitivity, or breakouts in formulas where it appears alongside other potentially irritating ingredients. This is informational, not medical advice.

Is Methylisothiazolinone safe for pregnancy?

While our analysis gives Methylisothiazolinone a safety score of 35/100 with a medium concern level, we recommend consulting your healthcare provider about any cosmetic ingredients during pregnancy or nursing. GlowLens provides general safety assessments - pregnancy-specific advice should come from your doctor or midwife.

Final Verdict: who should be most cautious with Methylisothiazolinone?

Acne-prone, oily, and reactive skin types may want to be more cautious with Methylisothiazolinone, since it carries a stronger pore-clogging signal. Other skin types generally have less to weigh. This is informational, not medical advice.

How we rate this ingredient

Rating sourced from official regulatory and scientific databases.Confidence: HighLast reviewed Jun 13, 2026
1 products analyzed containing MethylisothiazolinoneAnalyze a new product

Found in 1 Products

35

Power stick for her

medium

A potent preservative frequently linked to allergic contact dermatitis and restricted in leave-on products in many regions.

Showing all 1 of 1 products

Frequently Asked Questions

What is Methylisothiazolinone and why is it used?
We're still generating a detailed description for Methylisothiazolinone. Check back shortly - or scan a product containing this ingredient to speed things up. Across 1 products in our database, Methylisothiazolinone appears in various formulations. Use our free skincare ingredient checker to see how it interacts with other ingredients in specific products.
Will Methylisothiazolinone clog my pores? (Comedogenic Rating)
Methylisothiazolinone has an estimated comedogenic risk of 5/5 based on GlowLens ingredient scoring across 1 product analyses. A higher number signals a stronger pore-clogging tendency for acne-prone skin. This is informational, not medical advice.
Known Side Effects and Allergies: how concerning is Methylisothiazolinone?
Methylisothiazolinone currently scores 35/100, which places it in a moderate-concern band overall. The main practical consideration is skin irritation, sensitivity, or breakouts in formulas where it appears alongside other potentially irritating ingredients. This is informational, not medical advice.
Is Methylisothiazolinone safe for pregnancy?
While our analysis gives Methylisothiazolinone a safety score of 35/100 with a medium concern level, we recommend consulting your healthcare provider about any cosmetic ingredients during pregnancy or nursing. GlowLens provides general safety assessments - pregnancy-specific advice should come from your doctor or midwife.
Final Verdict: who should be most cautious with Methylisothiazolinone?
Acne-prone, oily, and reactive skin types may want to be more cautious with Methylisothiazolinone, since it carries a stronger pore-clogging signal. Other skin types generally have less to weigh. This is informational, not medical advice.