Ronidazole
General description
Ronidazole is a carbamate ester that is 5-nitroimidazole in which the hydrogens at positions 1 and 2 are replaced by methyl and (carbamoyloxy)methyl groups, respectively. An antiprotozoal agent, it is used in veterinary medicine for the treatment of histomoniasis and swine dysentery. It has a role as an antiprotozoal drug and an antiparasitic agent. It is a member of imidazoles, a carbamate ester and a C-nitro compound. It was first developed in the 1970s by the French pharmaceutical company Rhône-Poulenc as an antiprotozoal agent for use in veterinary medicine. It was initially developed as a more potent and effective alternative to the existing antiprotozoal drugs of the time. The drug was first introduced in Europe in the early 1980s under the brand name "Ridzol" and was initially used to treat infections caused by the protozoan parasite Tritrichomonas foetus in cattle. In the following years, it was also found to be effective against other protozoan parasites, such as Giardia and Trichomonas, in a variety of animal species, including cats, dogs, horses, and birds. Ronidazole was later approved for use in several other countries, including Australia and Canada, and is now widely used as a veterinary medication worldwide. In recent years, it has also been investigated for its potential use in human medicine, particularly in the treatment of infections caused by Helicobacter pylori, a bacterium that can cause ulcers and gastric cancer[1].
Application and Pharmacology
Ronidazole is a medication that is used in veterinary medicine to treat certain protozoal infections in animals. It is often used to treat infections caused by Giardia, a protozoal parasite that can cause diarrhea in dogs and cats. Ronidazole is also used to treat infections caused by Trichomonas, a protozoal parasite that can cause reproductive issues in birds. Pharmacologically, Ronidazole is a nitroimidazole derivative that acts by disrupting the DNA synthesis of protozoa, leading to their death. It is well-absorbed from the gastrointestinal tract and rapidly metabolized in the liver to form the active metabolite, 2-hydroxymethyl-5-nitroimidazole. This metabolite is then further metabolized to inactive metabolites that are excreted in the urine and feces. The recommended dosage of Ronidazole varies depending on the species, body weight, and the severity of the infection being treated. It is typically administered orally, either as tablets or a suspension. Treatment durations can range from several days to several weeks, depending on the specific infection being treated[2].
How is ronidazole given?
Ronidazole is given by mouth in the form of a capsule or liquid. It should be given with food prevent stomach upset. Measure liquid forms carefully. Wear gloves when administering this medication, and do not open or crush capsules. Wear gloves when handling feces, urine, vomit, saliva, or cat litter.
This medication should take effect within 1 to 2 days, and improvements in clinical signs should follow.
What if I miss giving my pet the medication?
If you miss a dose, give it when you remember, but if it is close to the time for the next dose, skip the dose you missed and give it at the next scheduled time, and return to the regular dosing schedule. If you are giving this medication once daily and it is within 12 hours of the next dose, skip the missed dose and wait for the next scheduled time.
Never give your pet two doses at once or give extra doses.
Are there any potential side effects?
Side effects may include vomiting or decreased appetite. Serious side effects may include tremors, severe tiredness, lack of appetite, incoordination, dizziness, fever, seizures, weakness, collapse, or abnormal behavior.
This short-acting medication should stop working within 24 hours, although effects can be longer in pets with liver or kidney disease.
Are there any risk factors for this medication?
Do not use ronidazole in pets that are allergic to it or other nitroimidazoles such as metronidazole. Dogs given this medication long term (for 2 years) had signs of testicular toxicity. It should be used cautiously in pets with seizures and very cautiously in pregnant animals; the benefits should outweigh the risks. If use in lactating animals is needed, use a milk replacer.
This medication is potentially carcinogenic to humans as it has been shown to cause cancer in mice, and has been shown to increase the rate of certain cancers in rats. As a precaution, wear gloves when administering this medication.
Are there any drug interactions I should be aware of?
The following medications should be used with caution when given with ronidazole: cimetidine, cyclosporine, fluorouracil, ketoconazole, lithium, oxytetracycline, phenobarbital, phenytoin, rifampin, tacrolimus, or warfarin.
Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking.
Is there any monitoring that needs to be done with this medication?
There is no specific monitoring that needs to be done while your pet is taking this medication. Your veterinarian may monitor your pet to be sure that the medication is working. Monitor your pet for serious side effects. Your veterinarian may check a polymerase chain reaction (PCR) test for the parasite although this test is not always accurate.
How do I store ronidazole?
Store this medication in the freezer in a tight container and protect from light, unless otherwise instructed on the label.
What should I do in case of emergency?
If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility.