Hypothyroidism drug-related

The prevalence of ANCAs and their relation to drug therapy have been examined in a consecutive series of 407 patients with Graves disease compared with 200 cases of autoimmune hypothyroidism and 649 controls (51). 

Hypothyroidism is treated with levothyroxine (T4). The drug is given once daily because of its long half-life. Steady state is achieved at 6-8 weeks. Toxicity is directly related to thyroxine levels and manifests itself as nervousness, heart palpitations and tachycardia, intolerance to heat and unexplained weight loss. 

Rovet J, Daneman D. Congenital hypothyroidism A review of current diagnostic and treatment practices in relation to neuropsychologic outcome. Paediatr Drugs 2003 5 141-149. 

During the early months of an infants postnatal life, TH deficiency may cause organ-related dysfunction and growth failure. Hypothyroidism of this period is caused by congenital problems (late appearance), autoimmune diseases and decreased TH production due to lack of iodine or drug effects. 

Uses Thyroid hormones, levothyroxine (T4), and triiodothyronine (liothyronine, T3) are used to treat hypothyroidism. Both overt and subclinical hypothyroidism are associated with dyslipidemia, and replacement with thyroid hormones lowers the concentrations of serum low-density lipoprotein (LDL) cholesterol and has other potentially favorable actions on lipoprotein metabolism [1 ]. Consequently, thyro-mimetic drugs, which mimic the actions of thyroid hormones, hold promise as lipidlowering agents. The development of some of these drugs was discontinued because of adverse reactions related to thyroid hormone-like actions, including possible death due to cardiac causes and adverse effects on bone [2 , 3 ]. 

Dose-relation Collateral Time-course Intermediate Susceptibility factors Genetic (the C-allele of the rs4149056 SNP in SLCOIBI on chromosome 12 COQ2 mutations) age (over 65 years) drugs (fibrates compounds that inhibit statin metabohsm, e.g. grapefruit) diseases (hypothyroidism trauma and physical exertion nephrotic syndrome)... 

Amiodarone, an anti-arythmic drug containing 37.2 % of organic iodine, may induce hypothyroidism and hyperthyroidism. Dysthyroidism can occur during treatment, but also many months after its discontinuation in patients with underlying thyroid disorders, as well as in subjects with apparently normal glands. We report the case of a patient who developed hypothyroidism followed by hyperthyroidism, related to amiodarone therapy. 

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