Get emergency medical help if you have any of these signs of an allergic reaction to Verapamil: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have any of these serious side effects:
- fast or slow heartbeats;
- feeling like you might pass out;
- fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
- restless muscle movements in your eyes, tongue, jaw, or neck;
- feeling short of breath, even with mild exertion;
- swelling, rapid weight gain; or
- nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
Less serious Verapamil side effects may include:
- constipation, nausea;
- skin rash or itching;
- dizziness, headache, tired feeling; or
- warmth, itching, redness, or tingly feeling under your skin.
This is not a complete list of side effects and others may occur.