Recovery of Active Pharmaceutical Ingredients from Unused Solid Dosage-Form Drugs

The concept of drug recycle by recovering active pharmaceutical ingredients (APIs) from unused tablets and capsules was demonstrated using acetaminophen, tetracycline HCl, and (R,S)-(±)-ibuprofen as case examples. The recovery process comprised three core unit operations: solid-liquid extraction, filtration, and crystallization. Recovery yields of 58.7 wt %, 73.1 wt %, and 67.6 wt % for acetaminophen, tetracycline HCl, and (R,S)-(±)-ibuprofen were achieved, respectively. More importantly, all of the APIs were of high purity based on high-performance liquid chromatography assay. The crystal forms of the recovered APIs were in conformity with the standards.