Slang consists of a lexicon of non-standard words and phrases in a given language. Use of these words and phrases is typically associated with the subversion of a standard variety (such as Standard English) and is likely to be interpreted by listeners as implying particular attitudes on the part of the speaker.
One caveat with D-mannose is that it is only effective with UTIs caused by E. coli infection. While this accounts for about 90% of cases, there are 10% that will not benefit from this treatment. In this case, supplements that help disrupt biofilms can be useful in treating and preventing UTIs.
A specific combination of dandelion root and leaf extracts of another herb called uva ursi taken by mouth seems to help reduce the number of UTIs in women. In this combination, uva ursi is used because it seems to kill bacteria, and dandelion is used to increase urine flow.