What side effects may I notice from receiving Famotidine?

Side effects that you should report to your doctor or health care professional as soon as possible:
-agitation, nervousness
-confusion
-hallucinations
-skin rash, itching

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
-constipation
-diarrhea
-dizziness
-headache

This list may not describe all possible side effects for Famotidine. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.