3 doctors weighed in:
My 18 yr old nephew just came in from a walk with his entire body covered in hives or a rash.It is recent, preceeds sweating but then he doesn't sweat?
3 doctors weighed in

Dr. Steven Machtinger
Internal Medicine - Allergy & Immunology
1 doctor agrees
In brief: Dizzy or coughing?
If after exercise someone has hives associated with difficulty breathing - coughing, wheezing, chest pain - nausea or vomiting, dizziness or light-headed think exercise-induced anaphylaxis.
Lie down with feet elevated & dial 911. If just hives give an antihistamine like Allegra (fexofenadine) 180 mg & head over to urgent care for evaluation. Could be a bee sting, exercise-induced hives, or food or drug allergy.

In brief: Dizzy or coughing?
If after exercise someone has hives associated with difficulty breathing - coughing, wheezing, chest pain - nausea or vomiting, dizziness or light-headed think exercise-induced anaphylaxis.
Lie down with feet elevated & dial 911. If just hives give an antihistamine like Allegra (fexofenadine) 180 mg & head over to urgent care for evaluation. Could be a bee sting, exercise-induced hives, or food or drug allergy.
Dr. Steven Machtinger
Dr. Steven Machtinger
Thank
1 comment
Dr. Bhavin Patel
Although, based on this history he may have an underlying process other than exercise-induced anaphylaxis. I would recommend an autoimmune chronic urticaria index, and thyroid antibodies studies to rule out other causes, including a tryptase level.
Dr. Yash Khanna
Family Medicine
1 doctor agrees
In brief: HIVES ALL OVER BODY
Hives all over body with itching feeling, no fever or any other symptoms are mostly due to allergy.
It can be some thing he ingested or came in contact with.If there are no other symptoms you can give him an antihistamine like Benadryl (diphenhydramine) every 4 hours and if it does not get better or there are other symptoms like fever, sore throa, cough, wheezing etc, then take him to your doctor or er.

In brief: HIVES ALL OVER BODY
Hives all over body with itching feeling, no fever or any other symptoms are mostly due to allergy.
It can be some thing he ingested or came in contact with.If there are no other symptoms you can give him an antihistamine like Benadryl (diphenhydramine) every 4 hours and if it does not get better or there are other symptoms like fever, sore throa, cough, wheezing etc, then take him to your doctor or er.
Dr. Yash Khanna
Dr. Yash Khanna
Thank
1 comment
Dr. Bhavin Patel
Have him evaluated by a board-certified allergist
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