- Cialis, Levitra or Viagra may cause headaches.
- Cialis, Levitra or Viagra may also cause upset stomach or diarrhea.
- Men who take Cialis, Levitra or Viagra may have back pain.
- Cialis, Levitra or Viagra may cause the face, chest or neck to appear red and to feel warmer than normal.
- Those men who take Cialis may experience a sore throat or stuffy nose. Those who take Levitra or Viagra may experience a stuffy nose.
- Men taking Cialis, Levitra or Viagra may experience memory problems.












