PARACETAMOL (Paracetamolum; synonym: Acetaminophen, Febridol, Paracetamol, Panadol etc.; GFH, SI. B) — soothing and antipyretic. N-acetaminophenol; With 8 H 9 NO 2 :
Inodorous crystal powder, white or white with creamy or pinkish shade. Let's difficult dissolve in water, we will easily dissolve in 95% alcohol, we will dissolve in acetone and solutions of caustic alkalis, it is almost insoluble on air; pier. weight 151,17; t ° pl 168 — 172 °.
Has soothing and febrifugal effect. According to a wedge, to data, on analgetic activity of P. concedes a little, and on febrifugal activity corresponds to acetylsalicylic acid (see). It is supposed that the specified P.'s effects are caused by its ability to inhibit a prostaglandinsintetaza in brain fabric that leads to reduction of education in c. the item of page of prostaglandins, the Crimea is attributed a role of mediators of fever and modulators of carrying out nervous impulses. Unlike salicylates and other groups of non-narcotic analgesics P. significantly does not influence activity of a prostaglandinsintetaza in peripheral fabrics, than, apparently, absence at it antiinflammatory properties is caused.
PARACETAMOL is well soaked up from went. - kish. a path also collects in blood in the maximum concentration in 40 — 60 min. after intake. Easily gets through various gistogematichssky barriers, including a placental barrier. It is inactivated in a liver by formation of conjugates of hl. obr. with glucuronic (to 63%) and a chamois (to 34%) to-tami, and also with cysteine (to 3%). Through kidneys it is allocated preferential in the form of the specified conjugates and in insignificant quantities (to 1%) — in not changed look. Elimination half-life from 2 to 4 hour. At disturbance of functions of a liver P.'s inactivation is carried out preferential by conjugation with cysteine and mercapturic to - that, and the period of semi-allocation increases till 8 and more o'clock.
PARACETAMOL apply as an anesthetic (it is frequent in a combination with analginum, pyramidon and other non-narcotic analgesics) at miozita, arthritises, neuralgia, a headache. In combination with myotropic spasmolysants and P.'s holinoblokator sometimes use at the pains connected with spasms of smooth muscles of internals.
Adult appoint inside on 0,2 — 0,5 g 2 — 3 times a day. To children aged from 6 up to 12 months appoint on 0,025 — 0,05 g, 2 — 5 years on 0,1 — 0,15 g, 6 — 12 years on 0,15 — 0,25 g 2 — 3 times a day.
The highest doses for adults inside: one-time 0,5 g, daily 1,5 g of P. formation of a methemoglobin (but to a lesser extent, than acetphenetidiene) can cause, allergic reactions. At prolonged use drug can break functions of a liver that is established on decrease in transaminazny activity. At the same time nausea, vomiting, formation of a methemoglobin, anemia, damages of a liver (are noted up to a centrolobular necrosis). Treatment of intoxications symptomatic. The hemodialysis and peritoneal dialysis are a little effective. Apply methionine and Cysteaminum to decrease in a hepatotoxic of P.
Form of release: powder, tablets on 0,2 g. As one of ingredients P. is a part of the drug «Skutamil-Ts». Storage: powder — in well corked container protecting from effect of light; tablets — in the place protected from light.
Bibliography: Clinical pharmacology, under the editorship of V. V. Zakusov, page 152, M., 1978; Ameer B. a. Greenblatt D. J. Acetaminophen, Ann. intern. Med., at. 87, p. 202, 1977, bibliogr.; Johnson G. K. a. Tolman K. G. Chronic liver disease and acetaminophen, ibid., p. 302; Proud-f o o t A. T. a. W r i g h t N. Acute paracetamol poisoning, Brit. med. J., v.3, p. 557, 1970.
V. K. Muratov.