Antithyroid Drug Treatment of Thyrotoxicosis in Young People

Summary

The investigators aim to establish whether biochemical control during anti-thyroid drug therapy in young people with thyrotoxicosis varies depending upon whether a 'block and replace' or 'dose titration' regimen is used. The investigators will also assess remission rates and the frequency of side-effects in the two treatment groups.

Conditions

• Paediatric Thyrotoxicosis

Interventions

PROCEDURE

Block and Replace

The primary objective of treatment is to maintain a euthyroid state with TSH and thyroid hormone levels in the local laboratory normal range. Carbimazole is commenced in a dose of 0.75 mg/kg/day (propylthiouracil - for dose see below) with the aim being to completely preventing endogenous thyroxine production. Thyroxine is then added in a low replacement dose as the thyroid hormone levels fall into the lower half of the laboratory normal range. The principle measure of control during the first 6 months will be thyroid hormone levels rather than TSH. Carbimazole is the preferred treatment because of the increased risk of hepatotoxicity with propylthiouracil but patients who are treated with propylthiouracil can also be recruited and randomised. 1mg of carbimazole is approximately equivalent to 10 mg of propylthiouracil.

PROCEDURE

Dose Titration

The primary objective of treatment is to maintain a euthyroid state with TSH and thyroid hormone levels in the local laboratory normal range. Carbimazole is commenced in a dose of 0.75 mg/kg/day until thyroid hormone levels fall into the local laboratory normal range. The dose is then reduced to 0.25 mg/kg/day with the intention of maintaining a euthyroid state as reflected by a free thyroxine and TSH within the normal range. Most paediatricians in the UK commence thyrotoxic children on carbimazole rather than propylthiouracil. Carbimazole is the preferred treatment because of the increased risk of hepatotoxicity with propylthiouracil but patients who are treated with propylthiouracil can also be recruited and randomised. The guidelines detailed above can be used in the knowledge that 1mg of carbimazole is approximately equivalent to 10 mg of propylthiouracil.

DRUG

carbimazole

Carbimazole 5mg and 20 mg tablets Administered as a once or twice daily regimen with total daily dose adjusted according to prevailing biochemistry

DRUG

propylthiouracil

50 mg tablets administered once daily with the dose adjusted according to the prevailing biochemistry

DRUG

thyroxine

25mcg, 50mcg and 100mcg tabletes administered once daily with the dose adjusted according to the prevailing biochemistry

Sponsors & Collaborators

• Newcastle-upon-Tyne Hospitals NHS Trust

  lead OTHER

Principal Investigators

• Tim Cheetham · Newcastle upon Tyne Hospiatls NHS Foundation Trust

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

2 Years

Max Age

16 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2004-07-31

Primary Completion

2014-12-31

Completion

2015-11-30

Countries

• United Kingdom

Study Locations