Small case studies in pregnant women with PAH indicate a low risk of harm, though caution is warranted. Dosage and strength for erectile dysfunction Sildenafil tablets for erectile dysfunction come in different strengths ranging from 25mg to mg. If you become pregnant while taking sildenafil, call your doctor. Your doctor or other health care professional can recommend one for you based on these factors, other health conditions you have and any other medicines you take. However, the dose is usually not more than 80 mg 3 times a day. Don’t view occasional erection problems as a reflection on your health or masculinity, and don’t automatically expect to have erection trouble again during your next sexual encounter. · Initial dose: 5 or 20 mg orally three times a day, 4 to 6 hours apart. Maximum dose: 20 mg orally three times a day. Injection: Initial dose: or 10 mg IV bolus three times a day. Comments: No greater efficacy was achieved with oral doses higher than the maximum recommended dose. tingling in the arms, feet, legs, or hands. numbness in the arms, feet, legs, or hands. headache. diarrhea. heartburn. trouble differentiating between colors like blue and green. seeing a blue. Drugs and Supplements. Sildenafil (Oral Route) Description and Brand Names. Before Using. Proper Use. Precautions. Side Effects. Products and services. Proper Use. Drug .