Quetiapine-induced hypokalemic periodic paralysis in a pregnant woman: a case report

Quetiapine-induced hypokalemic periodic paralysis (QIHPP) is a rare condition. Herein, we present the case of a 31-year-old pregnant Malay woman diagnosed with bipolar II disorder and QIHPP. She presented to the casualty department with a 2-day history of bilateral lower limb weakness and numbness. Her renal function tests showed moderate hypokalemia (2.5 mmol/L), whereas other investigations were normal. Quetiapine was suspected to be the cause, prompting a psychiatric referral to manage her acute condition. Balancing the risks of untreated QIHPP against the potential relapse of bipolar symptoms from quetiapine discontinuation or dosage reduction poses a significant treatment challenge for pregnant women with QIHPP. Finally, we reduced the quetiapine dosage after careful consideration, leading to the normalization of potassium levels and symptom resolution. Therefore, clinicians should be aware of this side effect when initiating or continuing quetiapine treatment in women of childbearing age or pregnant women with psychiatric disorders. It is crucial to monitor serum electrolytes, especially potassium, following quetiapine administration and warn patients about its potential side effects.