propylthiouracil and Muscle-Weakness

Periodic paralysis is a muscle disorder that belongs to the family of diseases called channelopathies, manifested by episodes of painless muscle weakness. Periodic paralysis is classified as hypokalemic when episodes occur in association with low potassium levels. Most cases are hereditary. Acquired cases have been described in association with hyperthyroidism. Diagnosis is made on clinical and biochemical grounds. Patients may be markedly hypokalemic during the episode and respond well to potassium supplementation. Episodes can be prevented by achieving a euthyroid state. This report describes a young gentleman presenting with thyrotoxic hypokalemic paraparesis. The condition needs to be considered in the differential diagnosis of neuromuscular weakness in the context of hypokalemia by the treating physicians.

Topics: Adult; Antithyroid Agents; Graves Disease; Humans; Hyperthyroidism; Hypokalemic Periodic Paralysis; Male; Muscle Weakness; Paraparesis; Potassium; Propranolol; Propylthiouracil; Thyroid Function Tests; Thyrotoxicosis; Treatment Outcome

Thyrotoxic periodic paralysis is rare in Caucasian populations, but affects approximately 2% of East Asians with thyrotoxicosis (13% of males, 0.17% of females). The presentation is characterized by abrupt-onset hypokalemia and profound proximal muscular weakness, and commonly occurs after carbohydrate loading or exercise.. To raise awareness of this condition through the description of a typical case of thyrotoxic periodic paralysis; to remind readers that, despite intravascular hypokalemia, total body potassium is normal and that correction must be done with caution; to highlight the differences in treatment compared to familial hypokalemic periodic paralysis.. We describe the presentation of a 36-year-old Filipino man with a background history of Graves disease. Over-administration of intravenous potassium was narrowly averted in this case.. It may be important to check thyroid function in patients presenting with acute paralysis, especially those of Asian origin. In patients with thyrotoxic periodic paralysis, administration of potassium, with cardiac monitoring and a total dose of <50 mmol, limits the dysrhythmia risk. Patients are likely to benefit from the prescription of non-selective beta-blockers until they become euthyroid. In contrast to familial periodic paralysis, regular oral potassium supplementation is ineffective in thyrotoxic periodic paralysis, and acetazolamide precipitates, rather than prevents, attacks.

Topics: Adrenergic beta-Antagonists; Adult; Antithyroid Agents; Graves Disease; Humans; Hypokalemia; Male; Muscle Weakness; Potassium; Propranolol; Propylthiouracil; Thyrotoxicosis

Hypokalemic periodic paralysis is a rare life-threatening syndrome, potentially reversible when detected at an early stage. Hypokalemia may also occur in other conditions characterized by muscle weakness. Acute myopathy associated with thyrotoxicosis has been described in Asian populations, although it seldom affects Caucasians or African-Americans. It can be difficult to recognize in western populations. Acute recurrent episodes of flaccid paralysis, symmetrically affecting the proximal muscles of the lower limbs, either following strenuous physical activity or carbohydrate overindulgence, is the usual presentation. Hypokalemia seems to result from transcellular shifts of potassium rather than losses. A case of thyrotoxic hypokalemic periodic paralysis occurring in a young Caucasian male diagnosed with Graves' disease is reported.

Topics: Antithyroid Agents; Humans; Hypokalemia; Male; Muscle Weakness; Paralysis; Propylthiouracil; Thyrotoxicosis; Young Adult

Topics: Adult; Anti-Arrhythmia Agents; Antithyroid Agents; Anxiety; Arrhythmias, Cardiac; Dyspnea; Graves Disease; Humans; Hypokalemic Periodic Paralysis; Malaysia; Male; Methimazole; Muscle Weakness; Neurologic Examination; Potassium; Propranolol; Propylthiouracil; Sleep Initiation and Maintenance Disorders; Tremor; Weight Loss