The present invention relates to inhalable particles comprising a stabilized amorphous form of tiotropium with a stabilizing agent. It also relates to inhalable particles comprising a stabilized amorphous form of tiotropium with a stabilizing agent mixed with one or more coarse excipients having a mean particle size of 15 to 250 μm. It also relates to a pharmaceutical composition comprising the inhalable particles of the invention, to a process for their preparation, and to their use for the preparation of a medicament for the treatment of asthma or chronic obstructive pulmonary disease (COPD).