The present invention relates used as an antidote for heavy metal poisoning and pharmaceutical formulations for pulmonary administration of the nanosize bisphosphonates. The present invention also relates to nanosize bisphosphonate particles prepared by the process of present invention and the formulations thereof. More particularly, the invention relates to bisphosphonate formulation that can be administered into lungs through pulmonary delivery as a dry powder inhaler or through nebulizer which has a sustained drug delivery in lungs for over a period of 24 hours.
