does itchy scalp = allergic reaction?

[LilacTea]

I have been using Paul Mitchell Shampoo One and The Conditioner for about two months and have developed a terribly itchy, irritated scalp. The irritation extends onto my neck and shoulders as well (from my hair touching my skin it appears) . This problem started about 2 weeks ago and has gotten worse over time. Is it possible I am allergic to an ingredient? Or, might it simply be dryness from the sulfates? It seems confusing that at first I had no reaction to it. I used Aubrey Blue Chamomile Shampoo and GPB Conditioner last night and was less itchy afterwards, which leads me to think the Paul Mitchell really is to blame. Has anyone else had a similar reaction to a sulfate shampoo? Note: until using my current PM stuff I had used only sulfate/cone free products for over a year. I had problems with dryness and tangles using natural products so I switched back to PM. It's looking like I need to go back to something more organic. Anyway any theories on the cause of my itchiness are welcome, since I want to avoid this problem in the future.

[Darkhorse1]

I've had reactions like this, but usually to any blue dye in the shampoo. For me, the reaction was instant, but allergic reactions can develop over time.

The best way to know? Stop using the product. Then, after 2 weeks, put some on the back of your hand and see if it develops the same reaction. If it does, i'm sure you could return the item.

[Messyhair]

Could it be build up that's making you itchy? Have you been clarifying while using the new product?

I do get 'the itchies' from shampoos all the time, but for me it tends to happen right after the first use.

[Purdy Bear]

It might be worth stopping the use of the two products to see if the itch lessens, if so then it will be the products. Then the only thing to do is to note the ingredients and do a series of trails to find out what your allergic too.

When you do have itching it can mean hair growing or hair loss, I get both.

[urara12]

my scalp is very senstive & tend to very itchy.I also have mild SD on my scalp. ( no dandruff) I can't use same s/c as every wash.
my Dr told me that if I using same S/C everytime I wash,
it could be develope the antibody. also he recommend me that use diluted S/C to try to reduse the risk to contact dermatitis .so I do diluted S/C ( I use spray bottle which it can make lot of forming)
I do routine 3-4 s/c . since I did change the way of shampoo
I don't get itchy scalp anymore.

[Nae]

I think an allergy can show up at any time without prior warning. I would be careful, it could be something else of course but I wouldn't rule out allergies either. Best of luck!