SUMMARY OF PRODUCT CHARACTERISTICS

Chanazone 1 g, oral powder for horses.

Chanazone (Denmark)

Chanbute 1 g, oral powder for horses (Austria, Germany)

Each sachet of 5 g contains:

Active substance:

Phenylbutazone 1 g.

For the full list of excipients, see section 6.1.

Oral powder

An off white to yellowish coloured granular powder

4.1 Target species

Horses (non-food producing horses).

4.2 Indications for use, specifying the target species

The product is indicated for the treatment of musculoskeletal conditions in the horse where relief from pain and areduction in the associated inflammation is required, e.g. in lameness associated with osteoarthritic conditions, bursitis,laminitis and soft tissue inflammation, particularly where continued mobility is considered desirable.

It is also of value in limiting post surgical inflammation, myositis and other soft tissue inflammation.

Phenylbutazone powdercan be used as an anti-pyretic where this is considered advisable e.g. in viral respiratory infections.

4.3 Contraindications

Do not use in animals with known hypersensitivity to the active substance.

Use is contra-indicated in animals suffering from cardiac, hepatic or renal disease, where there is the possibility ofgastro-intestinal ulceration or bleeding or where there is evidence of a blood dyscrasia.

Do not use in animals suffering from thyroid disease.

Do not use in animals with severe hypertonia.

Do not use in animals with lesions in the intestinal mucosa, caused by parasitic infestations.

4.4 Special warnings for each target species

The clinical effects of phenylbutazone can be evident for at least three days following cessation of therapy. This shouldbe borne in mind when examining horses for soundness.

FEI regards phenylbutazone as prohibited substance, it should be administered in accordance with FEI recommendations.

4.5 Special precautions for use

Special precautions for use in animals

Do not exceed the stated dose of 8.8 mg/kg/day as the therapeutic index of phenylbutazone is low.

Use in any animal less than 6 weeks of age or in aged animals may involve additional risk. If such use cannot beavoided animals may require careful clinical management.

Avoid use in any dehydrated, hypovolaemic or hypotensive animal as there is a potential risk of increased renaltoxicity.Keep water readily available during the treatment period to avoid dehydration.

NSAID’s can cause inhibition of phagocytosis and hence in the treatment of inflammatory conditions associated withbacterial infections, appropriate concurrent antimicrobial therapy should be instigated.

Special precautions to be taken by the person administering the veterinary medicinal product to animals

This product may cause hypersensitivity (allergic) reactions in those sensitized to phenylbutazone, either via skin contact or accidental inhalation.

People with known hypersensitivity to phenylbutazone, or any of the excipients, should avoid contact with this product.

If you develop symptoms following exposure, such as skin rash, you should seek medical advice and show the doctor this warning. Swelling of the face, lips or eyes, or difficulty breathing, are more serious symptoms and require urgent medical attention.

This product can be irritating to the skin and the eyes. Avoid contact with the eyes. In case of accidental eye contact, irrigate eyes with plenty of clean water. If irritation persists seek medical advice. Wash any exposed skin and hands after use.

Care should be taken to avoid ingesting the powder. In the event of accidental ingestion, seek medical advice and show the product packaging to the physician.

4.6 Adverse reactions (frequency and seriousness)

In common with other NSAIDs that inhibit prostaglandin synthesis, there may be gastric and/or renal intolerance. Thisis usually associated with overdosage and such events are rare. Recovery is usual on cessation of treatment andfollowing the initiation of supportive symptomatic therapy (see 4.10 for further information).

Blood dyscrasia may occur.

Ponies are very sensitive to gastric ulceration with this product, even at therapeutic doses (diarrhoea, ulceration in the mouth and hypoproteinaemia may also be seen).

If adverse reactions occur, treatment should be discontinued and the advice of a veterinarian should be sought.

4.7 Use during pregnancy, lactation or lay

Care should be exercised if administered to pregnant mares. Although no adverse effects of phenylbutazone on thefoetus or maintenance of pregnancy have been reported during field use, no definitive safety studies have been carriedout in the mare. Foetotoxic effects of phenylbutazone have been recorded in experimental animal species at high doselevels.

Use phenylbutazone in pregnant and lactating mares only according to a benefit/risk assessment by the responsible veterinarianAvoid use around time of parturition.

4.8 Interaction with other medicinal products and other forms of interaction

Do not administer other NSAID’s concurrently or within 24 hours of each other.

Concurrent administration of potential nephrotoxic drugs should be avoided.

Phenylbutazone induces hepatic microsomal enzyme activity.

There is a potential risk of increased renal toxicity after concurrent administration of aminoglycosides.

Concomitant use of glucocorticoids, other NSAIDs or anticoagulants increase adverse effects of phenylbutazone.

Therapeutic efficacy of diuretics may be reduced when used in combination with phenylbutazone-containing products

Phenylbutazone is extensively bound to plasma proteins. It may displace other drugs that are highly protein bound, e.g.some sulphonomides, warfarin or it may itself be displaced to produce an increase in non-bound pharmacologicallyactive concentrations, which can lead to toxic effects.

Concurrent therapy with other therapeutic agents should be undertaken with caution due to the risk of metabolicinteractions. Phenylbutazone may interfere with the metabolism of other drugs, eg warfarin, barbiturates with resultanttoxicity.

There is evidence to indicate that the pharmacokinetics of penicillin and gentamicinproducts may be affected by concurrentadministration of products containing phenylbutazone, with a possible reduction of therapeutic efficacy, since tissuepenetration may be reduced. The distribution in other drugs given concurrently may also be affected.

4.9 Amounts to be administered and administration route

For oral use.

The recommended dose rate is 4.4 – 8.8 mg/kg per day.

For each 450 kg bodyweight the following dosage guide should be used according to individual response:

Day 1 4.4 mg phenylbutazone/kg of bodyweight twice daily,(equivalent to two sachets or 10 g of the product twice daily).

Day 2-4 2.2 mg phenylbutazone /kg of bodyweight twice daily, (equivalent to one sachet or 5 g of the product twice daily) followed by 2.2 mg phenylbutazone /kg of bodyweight daily, (equivalent to one sachet or 5 g of the product daily) or on alternate days as required.

If no response is evident after 4-5 days, discontinue treatment. Hay may delay the absorption of phenylbutazone and sothe onset of a clinical effect. It is advisable not to administer hay immediately prior to, or during the administration ofthe product.

For ease of administration the productmay be mixed with a quantity of bran or oatsbefore each treatment.

4.10 Overdose (symptoms, emergency procedures, antidotes), if necessary

Overdosing may result in gastric and large intestinal ulceration and general enteropathy. Renal papillary damage mayalso occur with impaired renal function. Subcutaneous oedema, especially under the jaw, may become evident due toplasma protein loss.

In case of overdose CNS effects (excitement, seizures), hematuria and acidosis were observed. There is no specific antidote. If signs of possible overdosage occur, treat the animal symptomatically.

4.11 Withdrawal period

Not for use in horses intended for human consumption.

Treated horses may never be slaughtered for human consumption.

The horse must have been declared as not intended for human consumption under national horse passport legislation.

5. PHARMACOLOGICAL PROPERTIES

Pharmacotherapeutic group: Anti-inflammatory and Anti-rheumatic products, non-steroids

ATCvet code: QM01AAO1.

5.1 Pharmacodynamic properties

Phenylbutazone is a pyrazolone non-steroidal anti-inflammatory drug (NSAID) with analgesic, anti-inflammatory andantipyretic activity. These pharmacodynamic effects are achieved by the nonselective inhibition of prostaglandin synthetases (cyclooxygenases COX-1 and COX-2).

5.2 Pharmacokinetic particulars

The plasma elimination half-life of phenylbutazone in the horse varies from 3.5 - 8.0 hours. Normally peak plasmalevels are achieved approximately 2-3 hours after administration.

Oral bioavailability is high but absorption may bedelayed if administered on a full stomach. Hay in the diet may further delay absorption due to binding and so the onsetof a clinical effect.

Phenylbutazone binds heavily to plasma albumin.

Phenylbutazone is metabolised in the liver to oxphenbutazone, which also has similar pharmacological activity.

Further metabolism takes place to gamma-hydroxyphenylbutazone. Excretion is mainly via the urine.

6. PHARMACEUTICAL PARTICULARS

6.1 List of excipients

Glucose Monohydrate

Povidone

Apple Flavour

Xanthan Gum

Crospovidone

6.2 Incompatibilities

Do not mix this product with any other veterinary medicinal product.

6.3 Shelf life

Shelf life of the veterinary medicinal product as packaged for sale: 3 years.

6.4 Special precautions for storage

This veterinary medicinal product does not require any special storage conditions.

6.5 Nature and composition of immediate packaging

Paper foil sachets (Paper/LDPE/Foil/LDPE) containing 5g of powder per sachet.

Pack size: 100 sachets

Any unused veterinary medicinal product or waste materials derived from such veterinary medicinal products should be disposed of in accordance with local requirements.

7. MARKETING AUTHORISATION HOLDER

Chanelle Pharmaceuticals Manufacturing Ltd

Loughrea,

Co. Galway,

Ireland.

8. MARKETING AUTHORISATION NUMBERS

Vm 08749/4066

9. DATE OF FIRST AUTHORISATION

March 2016

10. DATE OF REVISION OF THE TEXT

May 2016

25 May 2016