PTU propylthiouracil

Propylthiouracil (PTU), but not methyl-mercaptoi-midazole (MMI), has an additional peripheral effect. It inhibits the monodeiodination of thyroxine to triiodothyronine by blocking the enzyme 5 mono-deiodinase [1]. In humans the potency of MMI is at least 10 times higher than that of PTU, whereas in rats PTU is more potent than MMI. The higher potency of MMI in humans is probably due to differences in uptake into the thyroid gland and subsequent metabolism, because in vitro inhibition of thyroid peroxidase by MMI is not significantly more potent than by PTU [1, 6]. Whether antithyroid drags have additional immunosuppressive actions is a matter of discussion [1, 2]. 

If thyroidectomy is planned, propylthiouracil (PTU) or methimazole (MMI) is usually given until the patient is biochemically euthyroid (usually 6 to 8 weeks), followed by the addition of iodides (500 mg/day) for 10 to 14 days before surgery to decrease the vascularity of the gland. Levothy-roxine may be added to maintain the euthyroid state while the thiona-mides are continued. 

Propylthiouracil (PTU) Anti-thyroid Protamine (Protamine) Heparin antidote... 

Propylthiouracil [PTU] [Antithyroid Agent/Thyroid Hormone Antagonist] Uses HypCTthyroidism Action X Production of Tg T4 conversion of T4 to Tg Dose Adults. Initial 100 mg PO q8h (may need up... 

Propylthiouracil (PTU) Inhibit thyroid peroxidase reactions block iodine organification inhibit peripheral deiodination of T4 and T Hyperthyroidism Oral duration of action 6-8 h delayed onset of action Toxicity Nausea, gastrointestinal distress, rash, agranulocytosis, hepatitis,hypothyroidism... 

Oral solution (Lugol s solution) 100 mg/mL potassium iodide plus 50 mg/mL iodine Oral potassium iodide tablets (generic, IOSAT, Thyro-Block) 130 mg Propylthiouracil [PTU] (generic)... 

Yu F, Zhao MH, Zhang YK, Zhang Y, Wang HY. Anti-endothelial cell antibodies (AECA) in patients with propylthiouracil (PTU)-induced ANCA positive vasculitis are associated with disease activity. Clin Exp Immunol 2005 139(3) 569-74. 

Antithyroid drugs such as propylthiouracil (PTU) and methimazole inhibit the iodination of tyrosyl residues as well as the coupling of monoiodotyrosine and diiodotyrosine into T3 and T4. In addition, PTU inhibits the peripheral conversion of T4 to T3. Unfortunately, there is a very high relapse rate with these drugs and a cure is very infrequent, if at all. The final alternative is thyroidectomy. In this case it is very difficult to determine exactly how much is to be excised. Not surprisingly, a consequence of surgery is the production of a hypothyroid individual who will require daily levothyroxine for the remainder of their life. 

The animals received drinking water containing 0,01% 6-propylthiouracil (PTU) ad libitum. After 2 days oral administration of drugs to be tested began and was... 

Hyperthyroidism may be treated with antithyroid drugs such as propylthiouracil (PTU) or methimazole (MMI), radioactive iodine (RAI e.g., I), or surgical removal of the... 

Nonsurgical treatments for Graves disease include administration of thion-amide antithyroid drugs, which include propylthiouracil (PTU) and methi-mazole, and/or treatment with radioactive iodine. The thionamides act by inhibiting the enzyme thyroid peroxidase, an enzyme on the apical membrane of the thyroid foUicnlar cell that faces the lumen. This enzyme catalyzes... 

Placental—most small molecular weight drugs cross the placental barrier, although fetal blood levels are usually lower than maternal. Example propylthiouracil (PTU) versus methimazole... 

Thioamides Propylthiouracil (PTU) and methimazole are small sulfur-containing molecules that inhibit thyroid hormone production by several mechanisms. The most important effect is to block iodination of the tyrosine residues of thyroglobulin (Figure 38-2). In addition, these drugs may block coupling of DIT and MIT. The thioamides can be used by the oral route and are effective in most patients with uncomplicated hyperthyroidism. Since synthesis of thyroid hormone rather than release is inhibited, the onset of activity of these drugs is usually slow, of-... 

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