Tadalafil is used to treat male intimate function problems (impotence or erectile dysfunction-ED) if you need this medicine you buy cialis 20mg online.the usual dose is 40mg two 20mg tablets, taken once a day. If you’re taking Cialis as you need it a healthcare provider will most likely get you started on a 10mg dose. never take 2 doses at the same time. never take an extra dose to make up for a forgotten one.this product may contain inactive ingredients, which can cause allergic reactions other problems to talk to your pharmacist or doctor.