An acid salt of sertraline, wherein the acid is citric acid, fumaric acid, malic acid, maleic acid, malonic acid, phosphoric acid, succinic acid, sulfuric acid, L-tartaric acid, HBr, acetic acid, benzoic acid, benzenesulfonic acid, ethanesulfonic acid, lactic acid, methanesulfonic acid or toluenesulfonic acid. Similarly, a solvate of sertraline HCl, wherein the solvent is methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, acetic acid, ethyl acetate, or propylene glycol.