Generic versions of sildenafil, vardenafil and tadalafil are available. These small differences affect the way each medication works, such as how quickly it takes effect and wears off, and the possible side effects. If a pregnant woman takes vardenafil, she should call her doctor. Your doctor will probably start you on an average dose of vardenafil tablets and increase or decrease your dose depending on your response to the medication. If you ever need emergency medical treatment for a heart problem, the health care providers who treat you will need to know when you last took vardenafil. Before taking vardenafil, tell your doctor and pharmacist if you are allergic to vardenafil,any other medications. · Less common. Arm, back, or jaw pain. blindness. blurred vision. chest pain, discomfort, or tightness. chest tightness or heaviness. chills. cold sweats. confusion. decreased vision. difficult or labored breathing. Common side effects of vardenafil may include: flushing (sudden warmth, redness, or tingly feeling); stuffy nose, sinus pain; headache, dizziness; upset stomach; or. back pain. Side effects of oral ED medicines are often mild. Common ones include: Flushing of the skin. Headache. Upset stomach. Visual changes, such as blue tinge to vision, sensitivity to light or blurred sight. Stuffy or runny nose. Back pain. Dizzy feeling.