The present disclosure relates to substituted amide compounds that are inhibitors of Fatty Acid Amide Hydrolase (FAAH), their stereoisomers, tautomers, prodrugs, polymorphs, solvates, pharmaceutically acceptable salts, and pharmaceutical compositions containing them. These compounds are useful in the treatment, prevention, prophylaxis, management, or adjunct treatment of all medical conditions related to inhibition of Fatty Acid Amide Hydrolase (FAAH), such as pain including acute and post operative pain, chronic pain, cancer pain, cancer chemotherapy induced pain, neuropathic pain, nociceptive pain, inflammatory pain, back pain, pain due to disease of various origin such as: diabetic neuropathy, neurotropic viral disease including human immunodeficient virus (HIV), herpes zoster such as post herpetic neuralgia; polyneuropathy, neurotoxicity, mechanical nerve injury, carpal tunnel syndrome, immunologic mechanisms like multiple sclerosis; sleep disorders, anxiety and depression disorders, inflammatory disorders, weight and eating disorders, Parkinson's disease, addiction, spasticity, hypertension or other disorders. The disclosure also relates to the process of preparation of the amide compounds. The present disclosure also relates to methods for the preparation of such compounds, and to pharmaceutical compositions containing them.