Regulation 23(1): amended, on 3 January 1980, by regulation 2 of the Misuse of Drugs Regulations 1977, Amendment No 3 (SR 1979/274).
Regulation 23(2)(e): amended, on 1 October 2008, pursuant to section 116(a)(ii) of the Policing Act 2008 (2008 No 72).
Regulation 23(3): amended, on 19 May 1978, by regulation 2(2) of the Misuse of Drugs Regulations 1977, Amendment No 2 (SR 1978/142).
Regulation 23(4): inserted, on 19 May 1978, by regulation 2(1) of the Misuse of Drugs Regulations 1977, Amendment No 2 (SR 1978/142).