Methods and formulations for making pharmaceutical compositions containing bupropion

A method of preparing a pharmaceutical tablet composition, comprising:

• forming a tablet core comprising bupropion, a water soluble gelling polymer at about 0.1% to about 5% by weight of the pharmaceutical tablet composition, and a binder at about 0.01% to about 2% by weight of the pharmaceutical tablet composition;
• coating the tablet core with a first coating layer, the first coating layer comprising:
• a copolymer of acrylate and methacrylate ester with quaternary ammonium groups at about 0.01% to about 2% by weight of the pharmaceutical tablet composition;
• and
• sodium lauryl sulfate at about 0.001% to about 1% by weight of the pharmaceutical tablet composition;
• and
• coating the first coating layer with a second coating layer, the second coating layer comprising an enteric polymer.

A method of preparing a tablet, comprising:

• forming a tablet core, comprising:
• forming a blend comprising bupropion and a binder at about 0.01% to about 2% by weight of the tablet;
• spraying a solution of a water soluble gelling polymer at about 0.1% to about 5% by weight of the tablet into the blend to create granules;
• drying the granules until the moisture content of the granules is below 1.5%;
• milling the granules to form milled granules;
• mixing the milled granules with a mixture comprising one or more lubricants and one or more anti-sticking agents to form a granule mixture;
• and
• pressing the granule mixture into the tablet core;
• coating the tablet core with a first coating layer, the first coating layer comprising copolymers of acrylate and methacrylates esters with quaternary ammonium groups at about 0.01% to about 2% by weight of the tablet, and an ionic surfactant at about 0.001% to about 1% by weight of the tablet;
• and
• coating the first coating layer with a second coating layer, the second coating layer comprising a methacrylic acid copolymer at about 0.01% to about 2% by weight of the tablet.