When oral medications might not be safe Check with your health care team before you take any medicine for erectile dysfunction. If you have any questions, ask your doctor or pharmacist. The medication Viagra is manufactured by Pfizer Canada Inc and it comes in 25 mg, 50 mg and mg dosage forms in a blister pack of 4 tablets. In Canada – Call your doctor for medical advice about side effects. Overdose If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call What about medications like Viagra® (sildenafil)? These medications (which also include tadalafil [Cialis ®] and vardenafil [Levitra ® ]) help men who can’t get an erection . The medication Viagra is manufactured by Pfizer Canada Inc and it comes in 25 mg, 50 mg and mg dosage forms in a blister pack of 4 tablets. Are over the age of 65 years; . Brand Name Viagra Common Name sildenafil In this drug factsheet: How does this medication work? What will it do for me? How should I use this medication? What form .