Skip to content
POM-VPS Prescription Required

Cydectin 20 mg/ml LA Solution for Injection for Sheep

Active ingredient: Moxidectin

Form

Injection

Species

Sheep

Manufacturer

Zoetis UK Limited

VMD MA No.

42058/5117

What it's used for

Treatment and prevention of mixed infections of gastro-intestinal nematodes, respiratory nematodes and certain arthropod parasites in sheep. Moxidectin is...

Full indications, dosage and side effects ↓
View official SPC (PDF)

The prescription itself has a price. See what practices near you charge for a consultation and the written prescription fee.

Paying less for Moxidectin

  1. 1

    Ask your vet for a written prescription

    They must provide one on request. Under the CMA Order the fee is capped at £21 from 2027.

  2. 2

    Fill it at a registered online retailer

    The CMA found online pharmacies 50–60% cheaper than practice dispensing on common medicines — typically £200–£300 a year.

Prescription required

Your vet must provide a written prescription on request. You can then purchase from any licensed online retailer.

Clinical information

Cydectin 20 mg/ml LA Solution for Injection for Sheep — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

Treatment and prevention of mixed infections of gastro-intestinal nematodes,
respiratory nematodes and certain arthropod parasites in sheep.
Moxidectin is indicated for treatment of infections caused by moxidectin sensitive
strains of:

. Haemonchus contortus (adults and L3)
. Ostertagia (Teladorsagia) circumcincta
. Trichostrongylus axei (adults)
. Trichostrongylus colubriformis (adults and L3)
. Nematodirus spathiger (adults)
. Cooperia curticei (macmasteri) (adults)
. Cooperia punctata (adults)
. Oesophagostomum columbianum (L3)

Amended pages: March 2025
AN: 01984/2024
. Chabertia ovina (adults)

Dictyocaulus filaria (adults)

. Oestrus ovis: L1, L2, L3

. Psoroptes ovis
The product has a persistent action and protects sheep against infection or re-
infection with the following parasites for the period indicated:
Species Days
Ostertagia (Teladorsagia) circumcincta
Haemonchus contortus
Trichostrongylus colubriformis
Psoroptes ovis
Persistent efficacy periods have not been established for parasite species other
than those included in the list above. Therefore, re-infection of animals on pasture
contaminated by parasites other than these remains possible before the 44-day
minimum persistency period demonstrated for specific species.
Do not use in sheep less than 15 kg bodyweight.
Do not inject the product by intravascular route. Intravascular injection may result in
ataxia, paralysis, convulsions, collapse and death. See item “Special precautions for
use in animals”
Do not use in cases of hypersensitivity to the active substance or to any excipients.
Sheep:
Very common
(>1 animal / 10 animals
treated):
Injection site swelling
Injection site inflammation
Rare
(1 to 10 animals / 10,000
animals treated):
Increased salivation
Ataxia
, Drowsiness
Depression
Very rare
(<1 animal / 10,000 animals
treated, including isolated
reports):
Neurological disorder
(such as collapse,
convulsion, paralysis)

Amended pages: March 2025
AN: 01984/2024
generally resolves without any treatment within 7 days
transitory, no specific antidote, no particular treatment is required: these
symptoms usually disappear within 24 to 48 hours
severe reactions may be fatal.
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian,
to either the marketing authorisation holder or its local representative or the national
competent authority via the national reporting system. See also the package leaflet
for respective contact details.
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.
-
misadministration of the product, or lack of calibration of the dosing device (if
any).

Amended pages: March 2025
AN: 01984/2024
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 macrocyclic lactones has been reported in Teladorsagia in sheep in a
number of countries. In 2008, throughout Europe, moxidectin resistance is very
rare; it has been reported in a single case involving a levamisole-, benzimidazole
and ivermectin-resistant strain of Teladorsagia circumcincta. Therefore the use of
moxidectin should be based on local (regional, farm) epidemiological information
about susceptibility of nematodes, local history of treatments and recommendations
on how to use the product under sustainable conditions to limit further selection for
resistance to anthelmintics. These precautions are especially important when
moxidectin is being used to control resistant strains.
Trials have shown that moxidectin is effective against certain strains of
Haemonchus contortus, Teladorsagia circumcincta Trichostrongylus .
resistant to benzimidazoles.
Psoroptes ovis is an extremely contagious external parasite of sheep and cattle. To
ensure complete control, great care must be taken to avoid re-infestation, 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.

Special precautions for use in animals
This product has been formulated specifically for subcutaneous injection in the base
of the ear of sheep and must not be given by any other route of administration or to
any other species.
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. If this occurs, it is unlikely that any product related
symptoms will be observed. In case of accidental self injection, seek medical
advice immediately and show the package leaflet or the label to the physician.

Amended pages: March 2025
AN: 01984/2024
Advice to Medical Practitioners in case of accidental self injection: Treat
symptomatically.
Special precautions for the protection of 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 sheep with the product, levels of moxidectin that are potentially toxic
to dung fly species may be excreted over a period of 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 beetle reproduction;
however, studies with incurred residues 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 to sheep,
treated animals should not have access to watercourses during the first 11 days
after treatment.
Other precautions
Not applicable.
The effects of GABA agonists are increased by moxidectin.
Do not store above 25°C. Keep the container in the outer carton in order to protect
from light.

Amended pages: March 2025
AN: 01984/2024
Meat and offal: 104 days.
Milk: Not permitted for use in dairy sheep, at any stage of life.
The withdrawal period is based solely on a single injection at the base of the ear.
5.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.

Medication costs adding up?

Pet insurance can cover prescription medications. Find the right policy for your pet.

Compare insurance

Find cheaper vets near you

Compare vet consultation prices in your area. Save on procedures and get a prescription to buy medications online.