I've yellow/white membranes in stool since month, abdominal pain, since 2weeks i developed acne in my face.acne were treated since 1yaer with clindamyci?

Possible infection: Taking antibiotics can alter the bacteria in your gastrointestinal tract and allow bad bacteria to multiply and produce infections which can be serious. Clindamycin useage is associated with the development of an infection caused by bacteria known as clostridium difficile. This requires treatment with another antibiotic. Evaluation and treatment needs to be started as soon as possible.

Clostridum difficile: You need to have your stool tested asap. Clindamycin can lead to an overgrowth of a bacterium called clostridium difficile or "c diff". The acne may be unrelated, many people get acne. I would do the stool work up first, then have the acne treated. I would favor Doxycycline by mouth for the acne if the gastrointestinal doctor is ok with that. Topical Retin-A med to the acne at night.