Green’s Dictionary of Slang

1. usu. in pl., marijuana; also attrib.

1928		Louis Armstrong [instrumental title] Muggles.
1930		J. Tully Shadows of Men 214: Hypo’s muggle cigarettes were cured in alcohol and dipped in perfume.
1939		C.R. Cooper Designs in Scarlet 148: [He] needs only a supply of muggles to make the score complete.
1946		Mezzrow & Wolfe Really the Blues 51: Ever smoke any muggles? [...] Man, this is some golden-leaf I brought up from New Orleans, it’ll make you feel good.
1950		Fads & Fancies 1 3: For those who don’t know, marijuana (or tea or weed or gauge — there is a whole new language here) is a drug [...] smoked in cigarettes known as reefers or mezzes or muggles. If you are in the habit of smoking [...] you are a ‘viper’ and when you are experiencing the full effects of the drug you are ‘high’.
1952		Lait & Mortimer USA Confidential 124: Many students at this institution of higher learning have graduated from muggles to hard stuff.
1971		‘Hassan-i-Sabbah’ Leaves of Grass 1: Gage / Muggles / Grass.
1980		S. McConville ‘Prison Language’ in Michaels & Ricks (1980) 525: Other names [for cannabis] include [...] muggles, and gage.
1985		‘Jennifer Blowdryer’ Modern English 79: joints (n): Muggles.
2001		ONDCP Street Terms 15: Muggie [...] Muggle — Marijuana.
2004		T. Dorsey Cadillac Beach 189: ‘Juju?’ said Bixby. ‘Muggles,’ said Mahoney. Miller turned to Bixby. ‘Marijuana.’.

2. (orig. US drugs) a marijuana cigarette; often a real cigarette with marijuana (occas. hashish) substituted for some of the tobacco and packed back inside it.

1935		N.E. Williams His Hi De Highness of Ho De Ho 36: They [i.e. marijuana cigarettes] are also called ‘muggles’.
1937		‘Boxcar Bertha’ Sister of the Road (1975) 222: He smoked the muggle leisurely, and began to brighten up.
1944		Marihuana Problem in City of N.Y. in Johnson Indian Hemp (1952) 34: The common names for the cigarettes are: muggles, reefers [...] tea, gage and sticks.
1956		(con. 1940s) J. Resko Reprieve 237: A reefer or muggle is blasted, banged, and blown — never smoked.
1969		R.R. Lingeman Drugs from A to Z (1970) 185: muggles [...] marijuana cigarettes.
1971		E.E. Landy Underground Dict. (1972).
1994		Rebennack & Rummel Under A Hoodoo Moon 216: He’s been smoking too many of them muggles.
2000		Indep. Rev. 16 Mar. 3: Reefers or muggles or joints or sticks of tea or whatever they were called that year.