10. Section 120 of the Principal Act is amended—
(a) by inserting in paragraph (4) (b) “or a pharmacist for the time being authorised, in writing or orally in the presence of a witness, by the Chief Pharmacist” after “institution”; and
(b) by inserting after subsection (5) the following subsection:
“(5A) Notwithstanding subsection (4), the residue left after a drug of dependence has been administered may be disposed of by a person referred to in subparagraph (4) (a) (i) or (ii) in the presence of another such person.”.