<s>[INST] Hello Doctor, I have been suffering with pain in my lower abdomen on the left side for the last two months. I consulted a doctor and got the following tests done- USG whole abdomen, Creatinine, Lipid profile, Thyroid, Urine Culture and Routine. The usg shows collection of fluid behind the uterus as told to me by the doctor who checked thye reports. He prescribed me Taxim. After taking those tablets the pain reduced but it is not completely curing. Please suggest..i m worried very much. Thanku Reena Pandey [/INST] Hi Reena,Thanks for your query.The commonest causes of little fluid in the narrow pouch (called Pouch of Douglas) between the rectum and uterus. A small amount of free fluid in the Pouch of Douglas is completely normal, and may just be an indicator of where a woman is in her menstrual cycle. The Pouch of Douglas typically holds a bit of fluid immediately after ovulation monthly. This fluid dissipates on its own as a woman continues on her cycle, and reappears during the next month's cycle.However, an infection of the peritoneal cavity can also cause fluid to build up in the pouch of Douglas. Infection is usually due to gonorrhea, fungal and trichomonal organisms.Common causes of fluid in the pouch are :-*    irritable bowel syndrome*    ovarian cysts*    Pelvic inflammatory diseaseI personally feel that Taxim or, preferably Azithromycin should be given along with anti-fungal (such as Fluconazole) + anti-amebic drug, such as metronidazole, tinidazole or secnidazole. Consult your doctor and apprise him of my opinion. I am certain that he agree with me, order required tests, and- based on the reports-  will prescribe suitable treatment as advised.If you find my response helpful and informative, do not forget an “excellent” rating to my answer, to encourage all doctors- engaged in social service- to render sound advice to the FREE queries. Fond regards and have a nice dayDr. Rakesh Karanwal </s>