An inhaler is provided with a closure which may be moved between a closed and open position in order to cover and uncover a mouthpiece. The closure is associated with a revolvable element including a restricting member. Movement of the closure from the open position to the closed position causes the revolvable element to revolve around an axis X thereby placing the restricting member in a restricting position which restricts relative movement between a container unit and the housing such that unintentional actuation of the inhaler is prevented. The inhaler is useful, for example, in the treatment of asthma.
