薬 (Kanji for medicine)

Onyomi

YAKU

The YAK was enjoying her medicine made from flowers. Actually she had wandered into a field of opium and was just high as hell.

くすり ( を飲む )

medicine.　薬を飲む　refers both to taking legal medcine and drugs.
★★★★★

薬局(やっきょく)

pharmacy ★★☆☆☆
薬 (medicine) + 局 (department) = 薬局 (pharmacy)

pharmacy (BOOBOO: 薬局 sells perscription drugs. . .the regular kind of Wallgreen's -ass drug store is 薬屋 (くすりや)）

睡眠薬(すいみんやく)

sleeping pill ★☆☆☆☆
睡眠 (sleep ) + 薬 (medicine) = 睡眠薬 (sleeping pill)

毒薬(どくやく) する

poison ☆☆☆☆☆
毒 (poison/ addict) + 薬 (medicine) = 毒薬 (poison)

regular ,intentional poison- as opposed to toxic pollutants or drugs.

	Meaning	Hint	Radical
薬	medicine	FLOWER	花
楽	enjoy	NO FLOWER

Opium medicine is made from FLOWERS.

If you're enjoying life, you don't need medical flowers, so NO FLOWER.