Pharmacotherapeutic group: other antiprotozoal agents.
ATCvet code: QA 07 AA 06.
Pharmacodynamic properties
Paromomycin has antiprotozoal activity, although its mechanism of action is unclear. In in vitro studies using HCT-8 and Caco-2 cell lines inhibitory activity against C. parvum was observed. Resistance of cryptosporidia to paromomycin has not been described to date. Nevertheless, the use of aminoglycosides is associated with the occurrence of bacterial resistance. Paromomycin may select for cross-resistance to other aminoglycosides.
Pharmacokinetic particulars
IV injection in lambs at a dose rate of 7 000 IU / kg showed that paromomycin is rapidly eliminated (T1/2 = 4.58 hours) and that the clearance (2.49 ml/min/kg) was relatively low showing probably limited liver metabolism.
The bioavailability of paromomycin when administered as a single oral dose of 50 mg paromomycin sulphate/kg bodyweight to lambs was 13%. With regard to the absorbed fraction, the mean peak plasma concentration (Cmax) was 2.68 mg/l, the mean time to attain the peak plasma concentration (Tmax) was 4 hours and the mean terminal half-life (t1/2, el) was 27.4 hours. The main part of the dose is eliminated unchanged in the faeces.
Environmental properties
The active ingredient paromomycin is very persistent in the environment.