A counter mechanism useable with a dry powder inhaler is disclosed. The mechanism features first and second indicator members rotatable about a central axis. The indicator members have counting indicia visible to indicate inhaler doses remaining or dispensed. A coupling transmits rotary motion from the inhaler to the second indicator member when the inhaler is charged with a dose. A slave wheel, rotatable about an axis offset from the central axis, has a drive transfer wheel on one face and a gear on an opposite face. The gear engages the second indicator member, the drive transfer wheel intermittently engages and rotates the first indicator member in response to rotary motion of the second indicator member.