A - Acts on the stool itself:
1 - Bulk-forming: need water to make Bulk-forming laxatives (methylcellulose, psyllium, polycarbophil)
2 - Stool surfactant: pull water & fat into stools &  lubricate stools (docusate, glycerin, mineral oil)
3 - Osmotic laxatives (think enema!): MOM, sorbital, lactulose, magnesium citrate, polyethylene glycol


B - Acts on the body:
1 - Stimulants (Senna, Bisacodyl)
2 - Opioid receptor anagonists (w/o impacting analgesic effects in CNS): alvimopan, methylnaltrexone, naloxegol

~Wonder Me!!!