Talk with your healthcare provider about your sex life and desired use. Counseling patients about the protective measures necessary to guard against sexually transmitted diseases, including Human Immunodeficiency Virus HIV should be considered. PDE5 is found in platelets. CIALIS should be used with caution in patients who have conditions that might predispose them to priapism such as sickle cell anemia, multiple myeloma, or leukemia , or in patients with anatomical deformation of the penis such as angulation, cavernosal fibrosis, or Peyronie’s disease. Tadalafil was administered to over men during clinical trials worldwide. There may be rare occurrences of priapism or painful, prolonged erections. This combination can cause dangerously low blood pressure.The maximum dose is 10 mg not more than once in every 48 hours. CrCl less than 30 mL/min or on hemodialysis: The maximum dose is 5 mg orally once every 72 hours. Once a day use for ED: CrCl 30 mL/min or greater: Data not available. CrCl less than 30 mL/min or on hemodialysis: Not recommended. Once a day use for BPH. Dosage. The dose of Cialis you need will depend on whether you’re taking it daily or as needed. Daily doses are often between and 5 milligrams (mg). The as-needed dose is usually 10 mg but can range from 5–20 mg. The typicaldose of Viagra is 50 mg. However, the dosage can range from 25– mg. This PDF document provides the full prescribing information for Cialis (tadalafil), a drug used to treat erectile dysfunction and benign prostatic hyperplasia. It includes indications, dosage, warnings, interactions, adverse reactions, and clinical studies.