Potential Causes of Forehead Bumps

Based on the ingredients provided and the reaction experienced by both you and your partner (small bumps resembling acne on the forehead after use), it's possible that one or more ingredients in the formulation are causing a reaction.

Several ingredients could potentially contribute to such a reaction in sensitive individuals or at certain concentrations:

• Vitamin B3 (Niacinamide): While generally beneficial for acne-prone skin and used at a moderate concentration (4%) in your formula with a high-purity version (Safe-B3), some individuals can still experience sensitivity, irritation, or breakouts, especially if their skin is sensitive or the formulation's pH is not ideal for their skin.
• 1,2-Hexanediol: This ingredient acts as a solvent, humectant, and preservative booster. At a 3% concentration, while within typical usage rates, it could potentially cause irritation or a reaction in some people.
• Pro Polymer (Acrylate Crosspolymer): As a gelling agent or film former, some polymers can be occlusive for certain skin types, potentially leading to clogged pores and bumps, although this is less common with modern cosmetic polymers.
• Phenoxyethanol SA: This is a preservative blend. Preservatives, in general, can sometimes cause contact dermatitis or irritation in sensitive individuals, which might appear as small bumps.

Other ingredients like Disodium EDTA, GlucoBright (Acetyl Glucosamine), Vitamin B5 (Panthenol), Dipotassium Glycyrrhizate, Atopic Telmesteine, and MOIST24 are generally less likely to cause acne-like reactions, often having soothing or moisturizing properties.

Since both you and your partner experienced a similar reaction, it suggests a sensitivity to an ingredient or the overall combination rather than an individual skin issue. To determine the exact cause, it would ideally require patch testing each ingredient individually. However, as a practical step, you might consider reducing the concentration of certain ingredients if you are making the product yourself, or discontinue use if the reaction persists.

If the bumps continue or worsen, it is recommended to consult a dermatologist.