Zermex 100 mg/ml LA Solution for Injection for Cattle

Unnecessary use of antiparasitics or use deviating from the instructions given in the
SPC may increase the resistance selection pressure and lead to reduced efficacy.
The decision to use the product should be based on confirmation of the parasitic
species and burden, or of the risk of infestation based on its epidemiological features,
for each individual herd.
Care should be taken to avoid the following practices because they increase the risk
of development of resistance and could ultimately result in ineffective therapy:
▪
extended period of time. Repeated use for an extended period, particularly when
using the same class of substances, increases the risk of resistance
development. Within a herd, maintenance of susceptible refugia is essential to
reduce that risk. Systematically applied interval-based treatment and treatment of
a whole herd should be avoided. Instead, if feasible, only selected individual
animals or subgroups should be treated (targeted selective treatment). This
should be combined with appropriate husbandry and pasture management
measures. Guidance for each specific herd should be sought from the
responsible veterinarian;
▪
misadministration of the product, or lack of calibration of the dosing device (if
any).
Suspected clinical cases of resistance to anthelmintics should be further investigated
using appropriate tests (e.g. Faecal Egg Count Reduction Test). Where the results of
the test(s) strongly suggest resistance to a particular anthelmintic, an anthelmintic
belonging to another pharmacological class and having a different mode of action
should be used.
Resistance to moxidectin has been reported in Cooperia spp. and
cattle.
Psoroptes ovis is an extremely contagious external parasite of sheep and cattle. To
ensure complete control, great care must be taken to avoid reinfestation, as mites
may be viable for up to 15 days off the animal. It is important that all animals which
have been in contact with infected ones are treated with an appropriate product.
Contact between treated, infected and untreated herds must be avoided until at least
seven days after treatment.
Resistance to moxidectin has been reported in Psoroptes ovis scab mites in sheep
and in cattle. Cases of side-resistance with other macrocyclic lactones (ivermectin
and doramectin) have been reported as well. The use of this product should take into
account local information about susceptibility of the target parasites, where available.

Revised: September 2025
AN: 01374/2025

Special precautions for use in animals
To prevent a possible anaphylactic type reaction, do not inject the product
intraevously.
In order to prevent abscesses, a strict aseptic technique is recommended.
The veterinary medicinal product has been formulated specifically for subcutaneous
injection in dorsal surface of the ear of cattle and must not be given by any other
route of administration or to any other species.
To avoid possible secondary reactions by the death of Hypoderma larvae in the spine
or the oesophagus of animals, it is recommended to administer a product effective
against Hypoderma larvae after the end of fly activity and before the larvae reach
their resting sites. Consult your veterinary surgeon on the correct timing of this
treatment.
Immunity to nematodes depends on adequate exposure to infection. Although not
normally the case, circumstances could occur in which anthelmintic control measures
might increase the vulnerability of cattle to re-infection. Animals may be at risk
towards the end of their first grazing season, particularly if the season is long, or in
the following year if they move onto heavily contaminated pasture. In such instances,
further control measures may be necessary.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
Avoid direct contact with skin and eyes.
Wash hands after use.
Do not smoke, drink or eat while handling the product.
Take care to avoid self-injection. Advice to Medical Practitioners in case of accidental
self injection: Treat symptomatically.
Other precautions regarding impact on the environment
Moxidectin fulfils the criteria for a (very) persistent, bioaccumulative and toxic (PBT)
substance; therefore, exposure of the environment to moxidectin must be limited to
the extent possible. Treatments should be administered only when necessary and
should be based on faecal egg counts or evaluation of the risk of infestation at the
animal and/or herd level.
Like other macrocyclic lactones, moxidectin has the potential to adversely affect non-
target organisms:
•
temporarily reduce the abundance of dung feeding organisms. Following
treatment of cattle with the product, levels of moxidectin that are potentially
toxic to dung fly species may be excreted over a period more than 4 weeks
and may decrease dung fly abundance during that period. It has been
established in laboratory tests that moxidectin may temporarily affect dung

Revised: September 2025
AN: 01374/2025
beetle reproduction; however, field studies indicate no long-term effects.
Nevertheless, in case of repeated treatments with moxidectin (as with
products of the same anthelmintic class) it is advisable not to treat animals
every time on the same pasture to allow dung fauna populations to recover.
•
should be used only according to the label instructions. Based on the excretion
profile of moxidectin when administered as the injectable formulation, treated
animals should not have access to watercourses during the 10 days after
treatment.