Topical Tramadol | Buy Tramadol | Opioids are the most powerful pain relievers, and therefore, traditional opioid analgesics remain the drug of choice for the medical treatment of severe acute pain syndromes and for progressive severe chronic illnesses (4). As a molecule, based on its physicochemical properties (5), tramadol appears to be a suitable transdermal agent. Also, its pKa is about 9.41; therefore, it is ionized and soluble over the pH range of interest (4).