If you drink tea with a diuretic effect, you'll need to use the bathroom more often.
医者は利尿剤を処方した。
The doctor prescribed a diuretic.
diuretic
diuretic
diuretic effect
Compound of 利 (ri, 'benefit, effect') and 尿 (nyō, 'urine'), literally 'promoting urine'. The reading りにょう follows standard on'yomi.