Sildenafil citrate (Viagra) is indicated for the treatment of erectile dysfunction, while Tramadol HCl (Tramal) is given in premature ejaculation performance in men. In Gaza Strip it is widely used to take these two drugs "in combination" for the previous purposes. The present work was conducted to assess the hematological and biochemical toxicity profiles of sildenafil & tramadol on domestic rabbits. Sixteen rabbits were randomly divided into two groups, the first one (10 rabbits) was given 1ml saline intramuscularly and kept as a control. The second group (6 rabbits) received 25 doses of sildenafil at a dose of 1.40 mg / kg b.wt. orally once/day and tramadol at a dose of 4 mg / kg b.wt. i. m. once/day for 25 days. It was found that administration of sildenafil and tramadol at these doses increased serum cholesterol, triglycerides, creatinine, urea and uric acid values. Activities of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were also increased following sildenafil & tramadol treatment to rabbits for 25 days. Moreover there was a significant decrease in serum total protein, albumin and globulin levels. Concerning hematological parameters, the more obvious changes were observed in the increment of white blood cells (WBCs), MCV and MCH and MCHC values. The decrease in hematocrit, hemoglobin (Hb), red blood cells (RBCs) and platelets (PLT) counts in response to the administration of the two drugs.