Thyrozol Side Effects

Minor adverse reactions eg, allergic skin reactions (itching, redness, rash) of varying degree occur frequently. They mostly take a mild course and frequently recede during continued therapy. Serious courses to the point of generalized dermatitis have been described only in isolated cases. Nausea, vomiting, epigastric distress, arthralgia, paresthesia, loss of taste, abnormal loss of hair, myalgia, headache, pruritus, drowsiness, neuritis, edema, vertigo, skin pigmentation, jaundice, sialadenopathy and lymphadenopathy.
Dru fever occurs rarely.
Disturbances in the sense of taste occur rarely; they can recede after discontinuation of Thyrozol; however, normalisation may take several weeks.
Changes in the blood count, granulocytopenia, thrombocytopenia, aplastic anemia, hypoprothrombinemia and nephritis can occur; agranulocytosis occur in about 0.3-0.6% of cases. They become apparent as inflammation of oral mucosa and pharynx, fever, formation of furuncles. In the case that any of these symptoms occur, especially during the 1st weeks of treatment, patients should discontinue Thyrozol immediately and have the physician perform a blood count check. The symptoms can still occur weeks or months after the start of therapy. In most cases, they recede spontaneously.
Isolated cases of pain in the joints have been reported, which generally develop gradually and also after several months of therapy. There are no signs of arthritis.
Isolated cases of jaundice due to impaired flow of bile or toxic inflammation of the liver have been described. The symptoms generally recede after discontinuation of Thyrozol.
The following have been described in isolated cases: Inflammation of lymph nodes (lymphadenitis), acute salivary gland swelling, decrease in the number of blood platelets and other blood constituents, inflammation of vessels and nerves, generally impaired sensitivity, loss of hair, Thyrozol-induced lupus erythematosus (autoimmune disease, the symptoms of which disappear after discontinuation of Thyrozol), as well as insulin autoimmune syndrome (with pronounced drop in blood glucose values).
Thiamazole reduces the energy requirement which was pathologically increased due to hyperthyroidism. This means that, with an unaltered diet, a gain in body weight can occur during treatment with Thyrozol. This is generally desired from a medical point of view.
Excessive dosage can cause hypothyroidism as well as diffuse thyroid growth. Consequently, the Thyrozol dose should be reduced after the metabolic activity of the thyroid gland has been normalized and/or a thyroid hormone should be given additionally. It is not appropriate to discontinue Thyrozol completely and continue treatment with thyroid hormones.
Further growth of the already enlarged thyroid under thiamazole therapy in spite of suppressed thyroid-stimulating hormone (TSH) levels is a result of the underlying disease and cannot be prevented by additional treatment with thyroid hormones.
The occurrence or deterioration of an eye disease which is typical in patients with hyperthyroidism (endocrine orbital disease) is largely independent of the course taken by the thyroid disease. Such a complication, by itself, is no reason to change the treatment regimen and is not to be regarded as a side effect of thiamazole therapy correctly carried out.
At low percentage, late hypothyroidism can occur after therapy with Thyrozol without any additional surgical measures. This is probably not a side effect of Thyrozol, but to be regarded as inflammatory process in the thyroid tissue occurring alongside the underlying disease.
If the patient have symptoms of agranulocytosis, granulocytopenia and thrombocytopenia drug fever or disturbances in the sense of taste, discontinue treatment with Thyrozol tablets and prescribe a different medication. Consult the doctor immediately if any side effects are experienced. Take any appropriate counter measures when necessary.
It should be noted that about 10% of patients with untreated hyperthyroidism have leukopenia (white blood cell count <4000/mm³) often with relative granulopenia.