If you have kidney problems, liver problems and heart attacks please prevent the usage of the drug. High as well as low blood pressure patients and people who have encountered stroke are advised to avoid the utilization of the medication. If you are allergic to ventolin or any other combinations of the drug then better to consult the doctor prior in usage of the medicine. People suffering from Retinitis Pigmentose as well as Sickle Cellanemia are instructed to prevent the usage of the drug. Dosage: ventolin happens to be an oral drug.this particular medication begins functioning following 45 minutes as soon as it is consumped. The impact normally persists up to 4 to 6 hours. Beyond its suggested dose might boost its negative consequences. Consult the doctor for prescription of the dosage as it depends upon the individual’s symptoms. Side Effects of ventolin: buy ventolin online may raise negative effects such as headache, stomach upset, nausea, sensitivity to light and chest pain, facial flushing,blurred vision.