Objective: The objective of the present work was to inhibit transformation of carbamazepine anhydrous to its dihydrate form in aqueous medium by adopting the co-crystal approach.Methods: Co-crystallization of carbamazepine and glucomannan as co-former was carried out by solution mediated phase transformation. The solution of carbamazepine and glucomannan in ethanol (95%) was agitated for 2 h and the co-crystals obtained were recovered after 24 h.Results: Co-crystal formation due to hydrogen bonding between carbamazepine and glucomannan as a co-former was confirmed by FTIR study. Inhibition of transformation of co-crystal of carbamazepine to carbamazepine dihydrate in aqueous medium was confirmed by SEM.Conclusion: Inhibition of transformation of carbamazepine co-crystal to its dihydrate form resulted in its improved dissolution. Dissolution efficiency of carbamazepine in its co-crystal was increased up to 79.26% within 30 min