It may start with an itch. You scratch it; before you know it, you have a rash. Sometimes a skin rash will show up without the itch. A skin rash can be caused from something simple like allergies. According to the Mayo Clinic, a skin rash could also mean internal disease. If you have any trouble breathing, stop reading and call 911.
Write a log of any new products, clothes or foods that have been brought into the house in the last few days. If there is nothing new, go back a week or two. Don't forget any new household cleaners or laundry products. Eliminate the new items until the rash gets better. Slowly introduce them back one at a time to find the culprit.
Inspect the rash. If your skin has raised bumps that appeared suddenly, call your doctor because this skin rash may be hives. If you have other symptoms--such as swelling in other parts of your body or trouble breathing--call 911 or go to the emergency room immediately. If not, try an antihistamine and a cool compress until they go away.
Look in the mirror. If your skin has a flushed appearance accompanied by little bumps, you might have Rosacea. Treatment might not be needed for mild cases. Talk to your doctor at your next appointment or immediately if it gets worse.
Take your temperature if you feel feverish. If the rash is red, raised or blister-like--or if it starts on your face and spreads downward accompanied with a fever, body aches, cough or sore throat--you might have measles or chickenpox. Contact your doctor. Stay away from any pregnant women as measles can cause birth defects. If fever and a rash are the only symptoms, go to step 5.
Check to see if the rash sufferer has been exposed to Fifth Disease if there's a fever and a bright red rash covering the cheeks. Fifth Disease is usually treated with cold medicine.
Call your doctor if your skip rash is red, yet there is no fever. This is especially important if you have recently taken a medication. This might be an allergic reaction to the medicine if the rash is red, possibly raised and isn't itchy. Do not stop taking the medication suddenly without discussing it with your doctor.
There are vaccines available for both Chickenpox and Measles. Prevent dry skin rashes by keeping your skin moisturised.
Try to avoid scratching as that can cause the rash to spread.