Brand: TRODAX ® 34% Solution


FORMULATION: «injectable» for subcutaneous injection.

ACTIVE INGREDIENT(S): nitroxinil: 340 g/L (=34%)

CHEMICAL CLASS of the active ingredient(s): halogenated phenol


PARASITES CONTROLLED (spectrum of activity)


10 mg nitroxinil/kg bw.


  • 14-20 kg: 0.5 ml product
  • 21-30 kg: 0.75 ml product
  • 31-40 kg: 1 ml product
  • 41-55 kg: 1.5 ml product
  • 56-75 kg: 2 ml product
  • >75 kg: 2.5 ml product


  • 14-20 kg: 0.5 ml product
  • 21-30 kg: 0.75 ml product
  • 31-40 kg: 1 ml product
  • 41-55 kg: 1.5 ml product
  • 56-75 kg: 2 ml product
  • >75 kg: 2.5 ml product


  • LD50 (acute oral) in rats: for the a.i. 170-450 mg/kg (for various salts)
  • LD50 (acute dermal) in rats: n.a.

Suspected poisoning? Read the article on nitroxinil safety in this site.

Withholding periods (=withdrawal times) for meat & milk (country-specific differences may apply: read the product label)

  • Meat: UK: Cattle: 60 days; Sheep 49 days.
  • Milk for human consumption: Not authorised for use in cattle and sheep producing milk for human consumption including the dry period. Do not use during the last trimester of pregnancy in heifers which are intended to produce milk for human consumption. Do not use within 1 year prior to the first lambing in ewes intended to produce milk for human consumption.

WARNING !!!: Never use on humans, dogs or cats

You may be interested in the following articles in this site dealing with the general safety of veterinary products:


Risk of resistance: LOW. No cases of field resistance to nitroxinil have been reported so far.

This means that if this product does not achieve the expected efficacy against the mentioned parasites, it is probably due to to incorrect use (the most frequent cause of product failure) rather than to resistance.

Alternative chemical classes/active ingredients to prevent resistance of liver flukes through product rotation:

These alternative products may not be available in all countries or may not be available as injectables.

There are also a few reports on liver fluke populations in sheep resistant to rafoxanide and closantel (both salicylanilides), probably with cross-resistance to nitroxinil, and also to clorsulon. So far resistance to these compounds seems to be less frequent than to resistance to benzimidazoles.

Learn more about resistance and how it develops.


Are the active ingredients of this product ORIGINAL* or GENERICS**?


*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.

COUNTRIES where this brand/product is marketed: UK, Ireland and some EU countries.
GENERIC BRANDS available? Rather few in most countries, if at all.

Click here to learn more about GENERIC vs. ORIGINAL drugs.

For an overview on the most used antiparasitic injectable brands click here.


TRODAX is the original nitroxinil brand developed by MAY & BAKER in the 1960s, later owned by MERIAL, now BOEHRINGER INGELHEIM.

Nitroxinil is a narrow spectrum anthelmintic, effective against liver flukes (adults & immatures >8 weeks old) and a few gastrointestinal  roundworms (e.g. Haemonchus spp, Bunostomum phlebotomum and Oesophagostomum radiatum). But it provides no control of numerous other gastrointestinal roundworm species that usually infect ruminants together with the mentioned species.

Nitroxinil has been replaced by more modern and effective flukicides in most countries, which are also safer. However, as fluke resistance to triclabendazole and albendazole increases, the need for alternatives is raising.

Where resistance of Haemonchus spp to other anthelmintics (benzimidazoles, levamisole, macrocyclic lactones) is already a problem, nitroxinil may be a suitable alternative.

In numerous countries (e.g. in Latin America) nitroxinil is often used combined with ivermectin, mainly in injectables for livestock, to add flukicidal efficacy.


This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics. 

Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.

In case of doubt contact the manufacturer or a veterinary professional.