Citramon P (Citramon P)

ASA: when ingested absorption is complete. During absorption, it undergoes presystemic elimination in the intestinal wall and systemic in the liver (deacetylated). The resorbed portion is rapidly hydrolyzed by cholinesterases and albumin and nesterase. therefore the half-life is no more than 15-20 minutes. In the body it circulates (75-90% in association with albumin) and is distributed in tissues as an anion of salicylic acid. Time to reach the maximum concentration - 2 hours Metabolized mainly in the liver with the formation of 4 metabolites, found in many tissues and urine. It is excreted by active secretion in the renal tubules in the form of salicylate (60%) and its metabolites. Removal of unchanged salicylate depends on the pH of the urine (with alkalinization of urine increases ionization of salicylates, their reabsorption worsens and the excretion is significantly increased). The rate of excretion depends on the dose: when taking small doses, the half-life period - 2-3 hours, with an increase in the dose may increase to 15-30 hours. In newborns, the elimination of salicylates is much slower than in adults.

the maximum concentration is achieved after 0.5-2 hours and is 5-20 μg / ml. Connection with plasma proteins - 15%. Penetrates through the blood-brain barrier. Less than 1 % from the accepted dose of paracetamol taken by the lactating mother penetrates into the breast milk. The therapeutically effective concentration of paracetamol in plasma is achieved with a dose of 10-15 mg / kg. Metabolised in the liver (90-95%): 80% enters the conjugation reaction with glucuronic acid and sulfates with the formation of inactive metabolites; 17% undergoes hydroxylation with the formation of 8 active metabolites, which are conjugated with glutathione with the formation of already inactive metabolites. With a lack of glutathione, these metabolites can block the enzyme systems of hepatocytes and cause their necrosis. In the metabolism also participates isoenzyme CYP2E1. The half-life is 1-4 hours. It is excreted by the kidneys in the form of metabolites, mainly conjugates, only 3 % at unchanged form. In elderly patients, the clearance of the drug decreases and the half-life increases. Caffeine: when ingested absorption is good, occurs throughout the intestine. Absorption occurs mainly due to lipophilicity, and not water solubility.

Maximum the concentration is reached in 50-75 minutes and is 1.58-1.76 mg / .p. Fast distributed in all organs and tissues organism; easily penetrates blood-brain barrier and placenta.

The volume of distribution in adults is 0.4-0.6 l / kg, in newborns - 0.78-0.92 l / kg. Communication with blood proteins (albumins) - 25-36%. Metabolism in the liver undergoes more than 90%, in children of the first years of life up to 10-15 %. In adults, about 80% of the dose of caffeine is metabolized to paraxanthin, about 10% - in theobromine and about 4% - in the theophylline, which subsequently are demethylated in monomethylxanthines, and then into methylated uric acids. The elimination half-life in adults is 3.9-5.3 hours (sometimes up to 10 hours). in newborns - 65-130 h (to 4-7 months of life decreases to value as in adults). Excretion caffeine and its metabolites is carried out kidneys (unchanged in adults 1-2%, in newborns - up to 85 %).