We strive to use primary sources and refrain from using tertiary references. Our guide to ED medication and heart disease provides more information on your options if you have ED and a cardiovascular medical condition. Call your doctor for medical advice about side effects. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. Damage to the Optic Nerve Levitra, as well as other ED medications such as Viagra and Cialis, are linked to cases of optic neuropathy, or optic nerve damage. These medicines all work well for ED. Depending on your personal needs, you may get better results from one of these medications.What Are Side Effects of Levitra? Levitra may cause serious side effects including: hives, difficulty breathing, swelling of your face, lips, tongue, or throat, chest . Common side effects of Levitra include facial flushing (reddening), headaches, stomach upset, diarrhea, flu-like symptoms, and nausea. Serious side effects of Levitra include .  · The Most Common Side Effects of Levitra. Headaches. Headaches are by far the most common side effect of Levitra. In fact, headaches are the most common side .