An inhaler device for administration of a dry powder to a patient includes a package containing a dose of the dry powder and a magnetic field generator, which produces a magnetic field in a vicinity of the package. The magnetic field causes motion of particles of the powder so as to deaggregate the powder in the package, whereby the powder is inhaled by the patient. Preferably, the package includes walls made of a flexible material, which vibrate under the influence of the magnetic field so as to impart the motion to the particles.