Box , Mission, KS If your pharmacy does not participate, you may be able to submit a request for a rebate in connection with this Savings Offer. This site is intended only for U. The decision, Teva Canada Ltd. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy NAION. The most common side effects of VIAGRA: headache; flushing; upset stomach; abnormal vision, such as changes in color vision such as having a blue color tinge and blurred vision; stuffy or runny nose; back pain; muscle pain; nausea; dizziness; rash. Generic versions of this low-dose form of sildenafil have been available in the U.It’s available by prescription for males ages 18 years and older. Side effects are not frequent and usually not severe. Viagra should only be taken once a day. Sildenafil (Viagra) is only approved by the FDA to treat erectile dysfunction in males. While some studies did look at the use of sildenafil (Viagra) nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or. And while generic Revatio is available only in a mg strength—Viagra comes in , , and mg tabs—not to worry: Your doctor can prescribe the most appropriate equivalent dose.