Vì vậy nó có thể được sử dụng một cách an toàn trong trường hợp suy thận. Nó không gây ra cơn động kinh. Tuy nhiên, nó có tác dụng nôn quan trọng đó là đôi khi rất khó để quản lý. Khi sử dụng liều ngậm dưới lưỡi là 0,2-0,4 mg mỗi 6-8 giờ. Liều tiêm thông thường là 0,3-0,6 mg tiêm bắp hoặc tiêm tĩnh mạch mỗi 6 giờ | PART I or only weakly active metabolites. Thus it may be used safely in cases of renal failure. It does not cause seizures. Nevertheless it has an important emetic effect that is sometimes difficult to manage. When used sublingually the dose is mg every 6-8 hours. The usual parenteral dose is mg intramuscularly or intravenously every 6 hours or mg kg per hour as an intravenous perfusion. 4 Tramadol although it has agonist effects on opioid receptors it also shows analgesic activity due to other mechanisms. It is a weaker analgesic than morphine about eight times . Since its half-life is slightly longer it is used parenterally at a dose of 100-150 mg every 6-8 hours mg kg per hour in perfusion . In cases of renal failure the drug accumulates in the bloodstream and it is advisable to increase the interval between doses. It favors the development of seizures in the conditions described for meperidine. Unlike most opiates it does not cause addiction. 5 Hydromorphone is eight times more potent as an analgesic than morphine. The recommended dose is mg every 3 hours intravenously or 1-2 mg intramuscularly or subcutaneously. A dose of mg hour may be given as a perfusion. 6 Fentanyl is 80 times more potent than morphine. It is hardly used parenterally in pancreatitis but the trans-dermal route which allows slow drug release is used especially to treat chronic pain. Recently this treatment has also been used successfully in acute pancreatitis see below . Effect on the sphincter of Oddi Traditionally several opioids including morphine have been rejected as treatments for pain in acute pancreatitis on the assumption that they increase biliary pressure. This was based on the findings of preliminary studies that indirectly measured biliary pressure after the use of these drugs. However opioids such as meperidine did not cause pressure changes and consequently it has become the narcotic of choice in acute pancreatitis. However as commented .
