What side effects may I notice from receiving Calan SR?

Side effects that you should report to your doctor or health care provider as soon as possible:

-allergic reactions (skin rash, itching or hives; swelling of the face, lips, or tongue)
-heart failure (trouble breathing; fast, irregular heartbeat; sudden weight gain; swelling of the ankles, feet, hands; unusually weak or tired)
-heartbeat rhythm changes (trouble breathing; chest pain; dizziness; fast, irregular heartbeat; feeling faint or lightheaded, falls)
-low blood pressure (dizziness; feeling faint or lightheaded, falls; unusually weak or tired)
Side effects that usually do not require medical attention (report to your doctor or health care provider if they continue or are bothersome):

-constipation
-facial flushing
-headache
-nausea
-stomach pain
-unusual swelling

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