In-depth

Complications

Low blood pressure (hypotension)

Low blood pressure (hypotension) can be a sign of good health or of a life-threatening condition. Find out more about hypotension's causes and treatment options.

Symptoms

Headache

Most headaches aren't caused by a serious illness, but some could be a sign of a life-threatening condition.

Hives and angioedema

Hives and angioedema — Comprehensive overview covers symptoms, causes, treatment of these common allergic disorders.

Runny nose

Runny nose: What's causing your sniffles?

Tests and diagnosis

Allergy skin tests

Itching, sneezing and swelling: Find out what's causing your allergy symptoms.

Apr. 26, 2012

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