Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Galantamine can cause serious skin reactions. Stop using  galantamine and call your doctor at once if you have the first signs of any skin rash, no matter how mild.
Call your doctor at once if you have:
chest pain, slow heart rate;
little or no urinating;
blood in your urine;
signs of stomach bleeding--bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds;
liver problems--nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
dehydration symptoms--feeling very thirsty or hot, being unable to urinate, heavy sweating, or hot and dry skin;
a light-headed feeling, like you might pass out; or
severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Common side effects may include:
nausea, vomiting, diarrhea, loss of appetite;
headache, dizziness; or
weight loss.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Galantamine side effects (more detail)
