Merck Manual

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Some Reasons to Call a Doctor*

Some Reasons to Call a Doctor*


Reasons to Call

Vomiting or inability to keep fluids down

Painful swallowing

Coughing that lasts more than 2 or 3 weeks or coughing up blood


Difficulty breathing

Symptoms that last more than 7 days

Black or bloody stools

More than 6 to 8 watery stools per day in children

Symptoms that last more than 7 days

Symptoms of dehydration (such as very dry mouth and armpits, confusion, and decreased urination), particularly in children and older people

Abdominal pain or fever > 100.4° (38° C)

A feeling that food is stuck in the throat

Development of or change in heartburn, particularly during exercise

Frequent heartburn, belching, or regurgitation

Persistent or severe abdominal pain

Persistent nausea

General problems

Unexplained weight loss

Dizziness or an about-to-faint feeling

Persistent fatigue

Sweating, especially heavy or cold sweats

Severe headache that peaks in intensity within seconds

Memory loss or confusion

Blurred or double vision

Slurred speech

Loss of balance or dizziness


Numbness or weakness in the arms, legs, or face

Nausea or vomiting with a new headache

Heart problems

Leg problems

Pain in the calves that worsens when walking

Swelling in the ankles or legs, particularly new swelling of one foot or leg

No periods by age 16

Sudden stopping of periods

A period that lasts much longer than usual or is excessively heavy

A sudden feeling of illness while using tampons

Severe or disabling cramps


Fever of 100.4° F (38° C) or above

A rash that is painful, involves swelling, or oozes

Swelling or redness in or around an eye

Problems with vision

Moderate or severe abdominal pain

Symptoms of dehydration, particularly in children and older people

Green, black, or bloody vomit

* The list of problems and the reasons to call a doctor are only a small sample.