Hi Amy,   I'd never heard of this before so did a quick search on the web and found the following information:   SMZ/TMP stands for SULFAMETHOXAZOLE / TRIMETHOPRIM - ORAL   Conditions for which this medication might be prescribed are listed below.    SMZ-TMP DS Oral is used to treat the following: Intestine Infection due to the Shigella Bacteria, Pneumonia caused by Pneumocystis Carinii, PCP Prophylaxis, Infection of the Middle Ear by H. Influenzae Bacteria, Infection of the Middle Ear caused by Streptococcus, Middle Ear Infection, Bacterial Infection with Chronic Bronchitis, Chronic Bronchitis caused by Streptococcus Pneumoniae, Chronic Bronchitis caused by Haemophilus Influenzae, Bacterial Urinary Tract Infection, Infection of Urinary Tract due to Enterobacter Cloacae, Urinary Tract Infection due to E. Coli Bacteria, Urinary Tract Infection caused by Klebsiella Bacteria, Infection of the Urinary Tract caused by Proteus Bacteria, Urinary Tract Infection caused by Morganella Morganii SMZ-TMP DS Oral may also be used to treat: Infection due to the Bacteria Vibrio Cholerae, Typhoid Fever, Infection due to Salmonella paratyphi Bacteria, Short-Term Infection with Diarrhea, Discomfort & Weight Loss, Infection due to a Brucella Bacteria, Brain/Spinal Cord Infection due to Listeria Monocytogene, Whooping Cough, Infection due to Nocardia Bacteria, Whipple's Disease, Infection due to Chlamydiae Species Bacteria, Highly Infectious Venereal or Sexually Transmitted Ulcer, A Sexually Transmitted Disease due to Chlamydia, Chronic Slow Progressing Ulcerative Granulomatous Disease, Chronic Skin Disease caused by a Fungus, Prevention of Toxoplasmosis, AIDS with Toxoplasmosis, Bacterial Infection of Heart Valve, Sinus Irritation and Congestion, Pneumonia caused by Bacteria, Diverticulitis, Continuous Bacterial Inflammation of the Prostate Gland, Skin Infection, Diabetic Foot Infection, Infection of Bone, Prevention of Plague Following Exposure to Plague, Colonization with Menigococcus Bacteria without Symptoms of Infection   Hope this helps, Elizabeth