Characteristics of the substance Tramadol
Tramadol hydrochloride is a white crystalline powder, odorless, bitter taste, soluble in water and ethanol.
Pharmacological action – analgesic (opioid).
Activates opiate receptors (mu, delta and kappa) on the pre- and postsynaptic membranes of the afferent fibers of the nociceptive system, in the brain and spinal cord, as well as in the gastrointestinal tract; promotes the discovery of potassium and calcium channels, causes hyperpolarization of the membranes and inhibits the conduction of nerve impulses. Slows the destruction of catecholamines and stabilizes their content in the central nervous system. The analgesic effect is due to a decrease in the activity of nociceptive and an increase in the antinociceptive systems of the body. It inhibits the cerebral cortex, has a sedative effect, inhibits the cough and respiratory centers, stimulates the starting zone of the vomiting center, the nucleus of the oculomotor nerve; causes spasm of sphincter smooth muscle.
After ingestion, it is quickly and completely absorbed (90%), absolute bioavailability – 68%, Tmax – 2 hours. Plasma protein binding – 20%. The volume of distribution depends on the method of administration and is 306 and 203 liters after oral or intravenous administration, respectively. Passes through the BBB and other histohematogenous barriers, including the placental, is secreted into breast milk. Biotransformation is carried out in the liver with the participation of CYP2D6 and CYP3A4 isoenzymes, mainly by N- and O-demethylation with subsequent conjugation. Identified 11 metabolites, one of them – mono-O-dezmetiltramadol (M1) – has pharmacological activity. Excreted mainly by the kidneys (90%, of which about 30% – unchanged) and the intestine (about 10%). In violation of the functions of the liver and kidneys (Cl creatinine less than 80 ml / min), elimination slows down.
Use of the substance Tramadol
Pain syndrome of medium and strong intensity (including with malignant neoplasms, injuries, in the postoperative period). Pain relief during painful diagnostic or therapeutic interventions.
Hypersensitivity; conditions accompanied by respiratory depression or severe CNS depression (alcohol poisoning, sleeping drugs, narcotic analgesics, and other psychoactive drugs); risk of suicide, propensity to substance abuse, simultaneous administration of MAO inhibitors (and a period of 2 weeks after their withdrawal), severe hepatic and / or renal failure, pregnancy (I term), breastfeeding (in the case of long-term use), children up to 1 year (for parenteral administration) and up to 14 years (for oral administration).
Restrictions on the use of
Opioid addiction, impaired consciousness of various origins, increased intracranial pressure, TBI, epilepsy, abdominal pain of unknown origin (acute abdomen), impaired renal function and / or liver.
Use during pregnancy and lactation
Appointment of tramadol is possible during pregnancy (II and III trimester) only under strict medical supervision, if the benefits to the mother outweigh the risk to the fetus.