soporiferous

"Item, on the said day, in the evening, a julep, hepatic, soporiferous, and somniferous, intended to promote the sleep of Mr. Argan, thirty-five sous."

From The Imaginary Invalid by Charles Heron Wall

At last the soporiferous fume of the wine lulled him into a gentle repose.

From Voltaire's Romances, Complete in One Volume by

The garden is also enriched by the cucumber, the soporiferous poppy, and the daffodil, and the acanthus.

From Library of the World's Best Literature, Ancient and Modern — Volume 4 by Hamilton Wright Mabie

If I rouse not now, I must have more soporiferous qualities than the Sleepers! or even than the Sleeping Beauty in the Wood, who took a nap of forty years.'

From The Wanderer (Volume 3 of 5) or, Female Difficulties by Fanny Burney

All this I was told; for, while the operation was performing, I lay in a profound sleep, by the force of that soporiferous medicine infused into my liquor. 

From Gulliver's Travels by Jonathan Swift