A medicament dispenser for use with a medicament carrier having multiple distinct medicament doses carried thereby and an internal mechanism for dispensing the distinct medicament doses carried by the medicament carrier. The mechanism comprises receiving means for receiving the medicament carrier; release means for releasing a distinct medicament dose from the medicament carrier on receipt thereof by the receiving means; an outlet, positioned to be in communication with the medicament dose releasable by the release means; indexing means for individually indexing the distinct medicament doses of the medicament carrier; and counting means for counting each time a distinct medicament dose of the medicament carrier is indexed by the indexing means. The counting means is a distinct electronic counter unit that is reversibly receivable by the medicament dispenser.