First-line anti-tuberculous drug names are often remembered with the mnemonic "RIPE," referring to the use of a rifamycin (like rifampin), isoniazid, pyrazinamide, and ethambutol. US practice uses abbreviations and names that are not internationally convened: rifampicin is called rifampin and abbreviated RIF; streptomycin is abbreviated STM. Other abbreviations have been widely used (for example, the notations RIF, RFP, and RMP have all been widely used for rifampicin, and the combination regimens have notations such as IRPE, HRZE, RIPE, and IREP that are variously synonyms or near-synonyms, depending on dosage schedules), but for clarity, the semistandardized abbreviations used above are used in the rest of this article. In this system, which the World Health Organization (WHO) supports, "RIPE" is "RHZE". (Both have mnemonic potential, as tuberculosis is named after tubercles (small tubers), and a tuber can be ripe and can be a rhizome.)