Ronidazole

Ronidazole is an antiprotozoal agent.

Efficacy of guar gum-based ronidazole capsules as a treatment for Tritrichomonas foetus infection in cats.[Pubmed:26662037]

J Feline Med Surg. 2017 Feb;19(2):177-184.

Objectives The aims of the study were to determine the in vitro drug release of guar gum-coated capsules of Ronidazole, and to evaluate the pharmacokinetics and efficacy of this formulation for the treatment of cats naturally infected with Tritrichomonas foetus. Methods The pharmacokinetics of Ronidazole were evaluated in five healthy cats and five cats infected with T foetus. In a second step, the clinical efficacy of these capsules was evaluated by a controlled, randomised, double-blind clinical trial performed in 47 infected cats from French catteries. In this study, cats were randomly allocated to either the Ronidazole treatment group (n = 25) or a placebo group (n = 22). Ronidazole (30 mg/kg) q24h for 14 days was administered to the treated cats. After 14 days of treatment, the presence of T foetus was tested by conventional PCR assay. Results In the pharmacokinetic study, a delayed peak plasma concentration was observed in healthy and infected cats, with no significant difference between these two groups (mean geometric mean of 9 h for time to maximum plasma concentration [Tmax], 21.6 microg/ml for time to maximum plasma concentration [Cmax] and 467.4 mug/h/ml for the area under the curve [AUC] in healthy cats; and 9.4 h for Tmax, 17.1 microg/ml for Cmax and 481 mug/h/ml for AUC in infected cats). In the clinical trial, T foetus was detected in 16% of cats from the treated group and 82% of cats from the placebo group at the end of the study ( P <0.001). No clinical signs of adverse drug reactions were observed. Conclusions and relevance Oral administration of guar gum-coated capsules of Ronidazole at a dose of 30 mg/kg once daily for 14 days delays the peak plasma concentration and eradicates infection in most cases.

Determination of the persistence of dimetridazole, metronidazole and ronidazole residues in black tiger shrimp (Penaeus monodon) tissue and their stability during cooking.[Pubmed:25372355]

Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2015;32(2):180-93.

The depletion of three banned nitroimidazole drugs - dimetridazole (DMZ), metRonidazole (MNZ) and Ronidazole (RNZ) - was investigated in black tiger shrimp (Penaeus monodon) following in-water medication. The highest concentrations of residues were measured immediately after the 24-h immersion (d0). At this time, MNZ and MNZ-OH residues were measured in shrimp tissue samples at concentrations ranging from 361 to 4189 and from 0.28 to 6.6 mug kg(-1), respectively. DMZ and its metabolites HMMNI ranged in concentration between 31,509 and 37,780 and between 15.0 and 31.9 mug kg(-1), respectively. RNZ and HMMNI concentrations ranged from 14,530 to 24,206 and from 25.0 to 55 mug kg(-1), respectively. MNZ, DMZ and RNZ were the more persistent marker residues and can be detected for at least 8 days post-treatment. MNZ-OH was only detectable on d0 following treatment with MNZ. HMMNI residues were only detectable up to d1 (0.97-3.2 mug kg(-1)) or d2 (1.2-4.5 mug kg(-1)) following DMZ and RNZ treatment, respectively. The parent drugs MNZ, DMZ and RNZ were still measureable on d8 at 0.12-1.0, 40.5-55 and 8.8-18.7 mug kg(-1), respectively. The study also investigated the stability of nitroimidazole residues under various cooking procedures (frying, grilling, boiling, and boiling followed by microwaving). The experiments were carried out in shrimp muscle tissue containing both high and low concentrations of these residues. Different cooking procedures showed the impact on nitroimidazole residue concentration in shrimp tissue. Residue concentration depleted significantly, but partially, by boiling and/or microwaving, but the compounds were largely resistant to conventional grilling or frying. Cooking cannot therefore be considered as a safeguard against harmful nitroimidazole residues in shrimp.

[Treatment of Tritrichomonas foetus in a cat colony with delayed release ronidazole tablets in the small intestine].[Pubmed:26591381]

Berl Munch Tierarztl Wochenschr. 2015 Sep-Oct;128(9-10):362-9.

Seven abyssinian cats (two male, five female) showed intermittent green-yellow mucous diarrhoea, sometimes an inflammation of the anal region and faecal incontinence even after long-time treatment with fenbendazole against Giardia. During necropsy of one of the cats, which had to be euthanized due to another disease, the gut wall of small and large intestine appeared macroscopically thickened. Histological examination indicated flagellates in the lumen of the intestine (initiating at the jejunum) and in the crypts. However Giardia could be excluded. in this case. By PCR of the faeces Tritrichomonas (T) foetus was diagnosed in five of six cats of this colony. Five remaining animals (another cat had to be euthanized) were treated with about 30 mg per kg BW Ronidazole p. o. (rededication; Ridzol 10% Bt(R), Dr. Hesse Tierpharma GmbH & Co. KG, Germany) daily over 14 days. The special gastro-resistant processing of the Ronidazole should ensure a targeted effects. Animals were treated consecutively, isolated from the other cats and were daily examined clinically and neurologically. Neurotoxic adverse effects appeared slightly, therefore--as a precaution--the treatment of two cats was paused for one day. After treatment of all cats, T. foetus wasn't diagnosed by PCR over the period of 345 to > 800 days in any cat. One animal had dubious findings in the ninth week after treatment. Hence it was still kept isolated from the group and PCR showed a negative result at all times afterwards. The treatment protocol shows that elimination of problematic protozoal infections is possible in cat colonies.

Use of Ronidazole and Limited Culling To Eliminate Tritrichomonas muris from Laboratory Mice.[Pubmed:27423157]

J Am Assoc Lab Anim Sci. 2016;55(4):480-3.

Tritrichomonas muris is occasionally identified during routine fecal screening of laboratory mice. Frequently, entire racks are affected, and because no effective treatment is available, culling of affected mice and rederivation by embryo transfer have been suggested. The current study evaluated whether treatment with Ronidazole, a nitroimidazole efficacious against T. fetus infections in cats, combined with limited culling was effective against T. muris in laboratory mice (Mus musculus). A subset (n = 39) of mice were treated with Ronidazole (400 mg/L in drinking water) for 15 d, after which 6 of the mice still shed T. muris. Consequently all mice in the affected rack received Ronidazole (500 mg /L in drinking water) for 25 d. All mice were retested by using pooled samples, and those positive for T. muris (except for a valuable breeding pair) were culled. The remaining mice continued to receive Ronidazole for another 17 d. At the end of the treatment period, all mice were tested (days 60 and 81) and were shown to be negative for T. muris. Over the following year, sentinel mice from the rack were tested every 3 mo and remained negative for tritrichomonads by fecal smear. Thus, a combination of limited culling and treatment with Ronidazole in the drinking water successfully cleared research mice of infection with T. muris.