Eltroxin Tablet 100mcg

TABLET

**Posology and method of administration** If the dose of _ELTROXIN_ is increased too rapidly, symptoms such as diarrhoea, nervousness, rapid pulse, insomnia, tremors and sometimes anginal pain where there is latent myocardial ischaemia may occur and the dosage must be reduced or withheld for a day or two, then restarted at a lower level. A pre-therapy ECG is valuable, as changes induced by hypothyroidism may be confused with ECG evidence of ischaemia. Due to a lack of data it is not appropriate to crush levothyroxine tablets and levothyroxine tablets without a score-line must not be halved. Levothyroxine tablets should preferably be taken on an empty stomach. Adults: Initially 50 to 100 mcg daily, preferably taken before breakfast, and adjusted at three to four week intervals by 50 mcg until attainment of clinical and biochemical euthyroidism. This may require doses of 100 to 200 mcg daily. With patients aged over 50 years, it is not advisable to exceed 50 mcg a day initially. Where there is cardiac disease, 25 mcg daily, or 50 mcg on alternate days, is more suitable. In this condition the daily dosage may be increased by 25 mcg at intervals of approximately four weeks. In younger patients, and in the absence of heart disease, a serum levothyroxine (T4) level of about 70 to 160 nanomoles per litre, or a serum thyrotrophin level of less than 5 milli-units per litre, should be aimed at. In those aged over 50, and/or in the presence of heart disease, clinical response is probably a more acceptable criterion of dosage then serum levels. In the event that a dose of 25 mcg is required, the adult may take a 50 mcg tablet on alternative days. Children: In congenital hypothyroidism and juvenile myxoedema, the largest dose consistent with freedom from toxic effects should be given. The dosage is guided by clinical response, growth assessment and appropriate thyroid function tests-clinically, normal pulse rate and absence of diarrhoea or constipation are the most useful indicators. Thyrotrophin levels may remain elevated during the first year of life in children with neonatal hypothyroidism due to resetting of the hypothalamic-pituitary axis. For infants with congenital hypothyroidism, a suitable starting dose is 25 mcg _ELTROXIN_ daily, with increments of 25 mcg every two to four weeks until optimal response is achieved. The same dosing regimen applies to juvenile myxoedema, except that the starting dose for children older than one year may be 2.5 to 5 mcg/kg/day. The calculated daily dose equivalent should be rounded to the nearest 25 mcg to determine the actual prescribed dose. In the event that a dose of 25 mcg is required, the child may take a 50 mcg tablet on alternative days. In patients whose medications include levothyroxine and known interfering agents, administration should be separated by at least 4 hours (see Section 4.5 – _please refer to the Product Insert/Patient Information Leaflet published on HSA for the full drug information_).