Hypo allergenic shampoo and conditioner for dry bleached hair

[HomeHell]

For the past week I've had an allergic reaction to something. Absolutely no idea what as I have not changed any products I eat or use on myself or around the home. I've been knocked for 6. I've still got it a low level reaction 1 week on despite steroids and anti histamines. It obviously is.somerhing I use frequently.
I've been so I'll this week I haven't eaten but have showered and washed my hair a few times so I'm going to try changing my shower products.

I have bleached highlighted hair and usually use a purple shampoo or shampoo for dry/chemically treated hair and a moisturizing conditioner for dry/chemically treated hair.
I want to switch to a hypo allergenic brand now to see if this will help.
Any suggestions or recommendations?

I have googled and there does not seem many products for dry hair just dry scalps.
Can anyone suggestive recommend a brand or product?

Check your products for Methylisothiazolinone. Up to 15% of the population is allergic to this and it's in loads of shampoos, makeup etc

I am very allergic to it. I also have coloured blonde dry hair and there are some great conditioners without this in. Expensive is Olaplex but amazing, mid range is American cream from lush. Cheap is the coconut hair masque from Superdrug. The last one I use as a conditioner rather than a mask

Sorry the Superdrug one is coconut water masque

Thank you so much Jeaux90. That's a great starting point and one ingredient to look out for.

Honestly I'd be surprised if it wasn't the culprit. The allergy specialist I saw said it's almost epidemic proportions of people who are allergic to this chemical.

Worse still you find it in some of the more luxury products like Clarins