An assistive device for a metered dose inhaler decreases the force required to operate the inhaler. The assistive device 1 has a body 3 with a passage 4 for receiving a replaceable conventional metered dose inhaler 2, and a foot 11 for supporting the inhaler mouthpiece. At least two symmetrically arranged levers 21 extend in a direction away from the body and parallel to an axis thereof. A proximal end 22 of each lever is attached to the body and the free opposite ends 23 of the levers may be moved towards and away from each other. An inwardly directed cam surface 24 on each of the levers engages a closed end of a canister 5 when the levers are moved together, to move the canister longitudinally and cause a dose of medicament to be dispensed from the canister. The foot may be telescopically length adjustable or the passage may be width adjustable, in order that the device can be retrofitted onto different sizes of inhaler.
