Propylthiouracil Tablet

Agranulocytosis is potentially the most serious side effect of propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) therapy. Patients should be instructed to report any symptoms of agranulocytosis, such as fever or sore throat. Leukopenia, thrombocytopenia, and aplastic anemia (pancytopenia) may also occur. The drug should be discontinued in the presence of agranulocytosis, aplastic anemia (pancytopenia), ANCA-positive vasculitis, hepatitis, interstitial pneumonitis, fever, or exfoliative dermatitis. The patient's bone marrow function should be monitored. Propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) can cause fetal harm when administered to a pregnant woman. Because the drug readily crosses placental membranes and can induce goiter and even cretinism in the developing fetus, it is important that a sufficient, but not excessive, dose be given. In many pregnant women, the thyroid dysfunction diminishes as the pregnancy proceeds; consequently a reduction of dosage may be possible. In some instances, propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) can be withdrawn 2 or 3 weeks before delivery.

If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be warned of the potential hazard to the fetus. Postpartum patients receiving propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) should not nurse their babies.

Rare reports exist of severe hepatic reactions including encephalopathy, fulminant hepatic necrosis, and death in patients receiving propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) . Symptoms suggestive of hepatic dysfunction (anorexia, pruritus, right upper quadrant pain, etc.) should prompt evaluation of liver function. Treatment with propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) should be discontinued promptly in the event of clinically significant evidence of liver abnormality, including hepatic transaminases in excess of 3 times the upper limit of normal.

Signs and Symptoms

Nausea, vomiting, epigastric distress, headache, fever, arthralgia, pruritus, edema, and pancytopenia. Agranulocytosis is the most serious effect. Rarely, exfoliative dermatitis, hepatitis, neuropathies, or CNS stimulation or depression may occur.

LD50: concentration of propyl-thiouracil in biologic fluids associated with toxicity and/ or death; the amount of drug in a single dose usually associated with symptoms of overdosage; or the amount of propylthiouracil (propylthiouracil (propylthiouracil (propylthiouracil tablet) tablet) tablet) in a single dose likely to be life-threatening.

Treatment

To obtain up-to-date information about the treatment of overdose, a good resource is the certified Regional Poison Control Center. Telephone numbers of certified poison control centers are listed in the Physician's Desk Reference (PDR). In managing overdosage, consider the possibility of multiple drug overdoses, interaction among drugs, and unusual drug kinetics in the patient. Protect the patient's airway and support ventilation and perfusion. Meticulously monitor and maintain, within acceptable limits, the patient's vital signs, blood gases, serum electrolytes, etc. The patient's bone marrow function should be monitored. Absorption of drugs from the gastrointestinal tract may be decreased by giving activated charcoal, which, in many cases, is more effective than emesis or lavage; consider charcoal instead of or in addition to gastric emptying. Repeated doses of charcoal over time may hasten elimination of some drugs that have been absorbed. Safeguard the patient's airway when employing gastric empyting or charcoal. Forced diuresis, peritoneal dialysis, hemodialysis, or charcoal hemoperfusion have not been established as beneficial for an overdose of propylthiouracil.

You should not use this medication if you are allergic to propylthiouracil, or if you are breast-feeding a baby.

If you have any of these other conditions, you may need a dose adjustment or special tests:

• liver problems; or
• a blood disorder.

FDA pregnancy category D. Do not use propylthiouracil if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

Propylthiouracil can pass into breast milk and may harm a nursing baby. Do not use propylthiouracil while you are breast-feeding a baby.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Major adverse reactions (much less common than the minor adverse reactions) include inhibition of myelopoiesis (agranulocytosis, granulopenia, and thrombo-cytopenia), aplastic anemia, drug fever, a lupus-like syndrome including solenomegaly, hepatitis, periartentis, and hypoprothrombinemia and bleeding. Nephritis, glomerulonephritis, interstitial pneumonitis, exfoliative dermatitis, and erythema nodosum have been reported. Reports of a vasculitic syndrome associated with the presence of anti-neutrophilic cytoplasmic antibodies (ANCA) have also been received. Manifestations of ANCA-positive vasculitis may include rapidly progressive glomerulonephritis (crescentic and pauci-immune necrotizing glomerulonephritis) sometimes leading to acute renal failure; fever; pulmonary infiltrates or alveolar hemorrhage; skin ulcers; and leucocytoclastic vasculitis.

Minor adverse reactions include skin rash, urticaria, nausea, vomiting, epigastric distress, arthralgia, paresthesias, loss of taste, abnormal Ioss of hair, myalgia, headache, pruritus, drowsiness, neuritis, edema, vertigo, skin pigmentation, jaundice, sialadenopathy, lymphadenopathy, vasculitis, glomerulonephritis, and taste perversion.

It should be noted that about 10% of patients with untreated hyperthyroidism have leukopenia (white blood cell count of less than 4,000/mm³), often with relative granulopenia.

Read the entire FDA prescribing information for Propylthiouracil (Propylthiouracil Tablet)