596881 Disclosed is a pharmaceutical composition liquid dosage form of phentermine (phenyl-tert-butylamine), said dosage form including a liquid carrier and suspended or dissolved therein one or more pharmaceutically active ingredient comprises one or more of phentermine HCl, and any other salt of Phentermine. Also disclosed is a Phentermine containing pharmaceutical composition administration apparatus, which apparatus includes a container and a dropper sized and dimensioned to permit a pharmaceutically active ingredient comprising one or more of phentermine HCl and any other salt of phentermine containing liquid dosage form to be accurately administered from 1 to 50 mg phentermine salt per administration thereof, and wherein the dropper is calibrated so that 20 drops of the Phentermine salt containing liquid dosage form are 1 mL, which is equivalent to from 1 to 100 mg phentermine salt per mL.