ACROSS

A3: half a mule

A4: speed effect

A6: naked oxycodone

A8: drug warriors

A10: injectors of old

A12: cheat

E2: drug treatment as punishment

E4: useless treatment

G10: "pop" singer

H12: psychiatric drug law reformer

K4: old police heroin test

DOWN

A3: cocky

B2: buy drugs

C5: chippers

E2: opium...

F6: French drugs: just say...

H2: tourniquet

H8: many drugs, many...

J6: addicts use

K1: "Heroin" singer

L10: chalky candy

M2: Papaverine flowers