Brief Answer:
You need to get blood investigations done..

Detailed Answer:
Hi..
Welcome to HEALTHCARE MAGIC..

I have gone through your query and can understand your health concerns..

As per your complain burning sensation in mouth along with rashes can occur due to a number of reasons and it may or may not be associated with each other..
The burning sensation of mouth can be due to BURNING MOUTH SYNDROME and it can occur due to a number of reasons like dry mouth, allergic reaction to certain medications,foods etc, Sjogen's syndrome, nutritional deficiency [ iron, folic acid, vitamin B12] , oral infections like thrush, acid reflux , Hormonal imbalances like in pregnancy, menopause, mensuration and in thyroid problems commonly in Hypothyroidism..
At times it can occur without any underlying cause..

The rashes can occur due to a number of conditions like Allergic reaction to certain medications, foods use of certain detergents to wash clothes, hormonal conditions like Thyroid problems,mensuration or menopause, fungal infections, and many more to go..

As you are a female it is possible that there may be nothing serious and both these conditions may be due to either Thyroid problems or fungal infection or hormonal imbalances leading to rashes as well as dry mouth..

Any final diagnosis can be given only after a blood investigation to rule out for allergies as well as thyroid profile..
You can consult a Physician and get evaluated and can revert me back with the investigations..
As I do need some more information like:
-Whether you are running with the menstruation cycle?
-Have you been gaining or loosing weight?
-Are you taking any medications?
-Do you have any known drug allergies?
-Do you have any itching or burning associated with the rashes?
-Do you have any white coating or dryness in mouth?

You can also send some additional information in case if you have any other associated problems..

Hope this information helps..

Thanks and regards.
Dr.Honey Nandwani Arora.

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