From Big Medical Encyclopedia

MERCAZOLIL (Mercazolilum; synonym: Antiroid, Basolan, Danantizol, Favistan, Mercazole, Methimazole, Methothyrin, Tapazole, Thiamazolum, Thycapzol, Thymidazol etc.) — the synthetic anti-thyroid (thyreostatic) medicine applied to treatment of a diffusion toxic craw; as well as other derivative thioureas and a mercaptoimidazole, actively slows down synthesis and secretion of thyroid hormones by suppression of the corresponding fermental systems of a thyroid gland. Like other anti-thyroid substances lowers basal metabolic rate.

White or yellowish crystal powder with a slight specific smell and bitter taste. Let's dissolve in water (1: 7,5) and in alcohol (1: 10).

At severe forms of a diffusion toxic craw of M. is the main means of conservative therapy. In its these cases appoint on 0,01 g 3 — 4 times a day.

At nek-ry patients at a severe form of a thyrotoxicosis the daily dose of M. can be raised to 40 mg and more. After approach of remission (in 3 — 6 weeks) the daily dose is reduced every 5 — 10 days by 0,005 — 0,01 g and gradually select the minimum maintenance doses (0,005 g once a day, every other day or 1 time in 3 days) before obtaining lasting therapeutic effect. At easy and average forms of a thyrotoxicosis of M. appoint 0,005 g 3 — 4 times a day. Accept it inside after food. Usually treatment is continued within 1 — 1,5 years since early drug withdrawal can lead to a recurrence of a disease. In the same doses of M. apply by preoperative preparation for a strumectomy. The highest doses of M. for adults inside: one-time 0,01 g, daily 0,04 g

of M. are usually well transferred by patients, however at its use the granulocytopenia up to an agranulocytosis can develop. Apply nucleinate of sodium, leucogenum, pentoxyl to treatment of this complication, in the presence of a relative lymphocytosis — glucocorticoids (a hydrocortisone, Prednisolonum, etc.). At M.'s reception allergic manifestations — fever and skin rashes can be observed, a small tortoiseshell is more often. These complications demand drug withdrawal (in nek-ry cases pass to use of other thyreostatic means). M. can sometimes exert toxic impact on a liver that is shown by increase in concentration of bilirubin in blood. In these cases thyreostatic therapy is immediately stopped. At M.'s overdose the hypothyroidism can develop, in these cases it is necessary to reduce a dose of drug or for a while to stop M.'s treatment, purpose of small doses of Thyreoidinum is sometimes reasonable.

In an initiation of treatment of M. the so-called goitrogenic effect (a hyperemia, a hyperplasia and a hypertrophy of a thyroid gland) is possible, then this phenomenon connected with increase in thyritropic function of a hypophysis passes.

Contraindications to M.'s use: nodal craw, retrosternal and intrathoracic localization of a craw, pregnancy and feeding, liver failure, leukopenia and granulocytopenia. It is not recommended to appoint M. together with drugs, to-rye can cause a leukopenia (pyramidon, streptocides and so forth).

Form of release: tablets on 0,005g. Store as drugs of the list B, in the dry place protected from light.

See also Anti-thyroid means .

Bibliography: Klyachko V. R. Topical issues of conservative treatment of a toxic craw, M., 1965; Mashkovsky M. D. Pharmaceuticals, p.1, page 552, M., 1977; To Milk III of t. Therapy of endocrine diseases, the lane from Romanians., Bucharest, 1969.

A. G. Mazowiecki.