That has opened an opportunity for trading on the black market. This can happen if you are sick with fever, diarrhea, or vomiting; sweat a lot; or do not drink enough liquids. However, sometimes, packages can get lost or stuck at customs. 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. The products discussed in this site may have different product labeling in different countries. No reference to the e-pharmacy or medication appears on the parcel. Or just pop into a private clinic or hospital. · You can take the drug 30 minutes to 4 hours before you anticipate sexual activity. Based on how well you respond to this dosage and any side effects you have, your doctor may either increase your. September 27, – AM. AFP. Viagra. THAILAND has approved an affordable generic version of the anti-impotence drug Viagra to go on sale next week as the country . Works as good as Viagra, no prescription required, at “real” pharmacies around Thailand. Sidegra – generic viagra and no prescription required. Don’t go to a big-name pharmacy, .