Test

How to Patch Test

There isn't a single way to patch test, what I've outlined below is the most comprehensive / elaborate / way that I personally can think of. But if there's another way that works for you, you should be following that.

Application Procedure:

• Wash the area that you want to patch test on and apply the product there, on an area large enough for you to notice a reaction.
  If it's a rinse off product, wash the product of after 10 to 15 minutes
  If it's a leave on product, just let it absorb and sink in. Don't wash it off

** Step I Start off patch testing in a place that that is easily hidden in case of a reaction**

Somewhere like the inner arm / behind the ear. Watch for reactions for around 96 hours [3]. (In allergic contact dermatitis, the elicitation time depends on the characteristics of the sensitizer, the intensity of exposure, and degree of sensitivity. Lesions usually appear 24 to 72 hours after the exposure to the causative agent and reach their peak at approximately 72 to 96 hours.) This is to eliminate the possibility of allergy. If you don't see any reactions then move on to Step II.

** Step II Patch Test in your least problematic areas**

Apply the product in a place where you are most unlikely to break out in. Like side of the jaw or neck. Watch our for a reaction for however long your skin normally takes to react. Could be a few hours, 24 hours, 48 hours etc. (The acute irritant reaction usually reaches its peak quickly, within minutes to few hours after exposure) [4]. The reasoning behind this step is, if you're breaking out where you never do, you probably will break out where you normally do. If your skin doesn't react, then onto Step III.

** Step III Patch Test carefully, in your problematic areas **
Analyse what you're most prone to, as mentioned above, and apply the product in small (but still big enough for you to notice) patch, based on your proclivities. Could be cheeks or forehead.
To check for irritation---The area where you're most sensitive
To check for clogs or acne----The area in which you experience this the most
Wait and watch for reactions. If you don't react, apply again every day for a week or so.

** Step IV Full Face Patch Test **
Sounds idiotic, but what I mean is introduce products slowly on full face. Once or twice and week and move on to daily. I don't mean this only for actives, but for every single product that you're newly introducing into your routine. This gives your skin a chance to get used to the product especially heavier ones like moisturisers, that are more likely to clog acne prone skin.
Still no reaction? You're good to go.