SUMMARY OF PRODUCT CHARACTERISTICS

1. NAME OF THE VETERINARY MEDICINAL PRODUCT

Duofast Intramammary Suspension

2. QUALITATIVE AND QUANTITATIVE COMPOSITION

Qualitative Composition

Trimethoprim and Sulfadiazine

Quantitative Composition

Each 8g syringe contains 40mg trimethoprim and 200mg sulfadiazine.

For a full list of excipients, see section 6.1

3. PHARMACEUTICAL FORM

Intramammary suspension

A white to off-white suspension for lactating cattle

4. CLINICAL PARTICULARS

4.1 Target Species

Cattle (lactating)

4.2 Indications for Use, Specifying the Target Species

The product is an intramammary suspension for the broad spectrum treatment of clinical mastitis in the lactating cow.

The product is effective against gram-positive and gram-negative bacteria including Streptococcus agalactiae, Streptococcus dysgalactiae,Streptococcus uberisand other streptococcal species, staphylococcal spp, Actinomyces pyogenes, Eschericha coliand other gram-negative bacteria.

4.3 Contraindications

Do not use in cattle with known sulphonamide sensitivity

4.4 Special Warnings for Each Target Species

Do not use in cattle with hepatic damage or blood dyscrasias.

4.5 Special Precautions for Use

i. Special precautions for use in animals

None

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

Take care to avoid skin and eye contact. Gloves should be worn whilst handling this product. Wash hands and exposed skin after use.

Sulphonamides may cause hypersensitivity (allergy) following injection, inhalation, ingestion or skin contact. Hypersensitivity to sulphonamides may lead to cross reactions with other antibiotics. Allergic reactions to these substances may occasionally be serious.

1. Do not handle this product if you know you are sensitive to sulphonamides.

2. If you develop symptoms following exposure such as a skin rash, you should seek medical advice and show the doctor this warning.

4.6 Adverse Reactions (Frequency and Seriousness)

None

4.7 Use During Pregnancy, Lactation or Lay

Safe for use during pregnancy and lactation

4.8 Interaction with other Medicinal Products and Other Forms of Interaction

None known

4.9 Amounts to be Administered and Administration

The contents of one syringe should be infused into each affected quarter via the teat canal, immediately after milking, at 12 hour intervals for three consecutive milkings. Clean and disinfect the teat before each treatment.

The syringe must only be used once.

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

Not applicable.

4.11 Withdrawal Period(s)

Cattle: Meat – 7 Days

Milk – 48 Hours

5. PHARMACOLOGICAL PROPERTIES

Pharmacotherapeutic group: Antibacterial for intramammary use, Sulfonamides and trimethoprim for intramammary use, Trimethoprim and derivatives

ATC Vet Code: QJ51EA

5.1 Pharmacodynamic properties

Duofast contains trimethoprim and sulfadiazine as the active ingredients which act with a unique "double-blockade" mode of action. Each component disrupts a different vital link in the metabolic chain used by susceptible bacteria to make nucleic acids and proteins.

Sulfadiazine inhibits the incorporation of p-amino benzoic (PABA) acid into dihydrofolic acid.

Sulfadiazine specifically competes with PABA for the enzyme dihydropteroate synthetase, this selective bacteriostatic action depending on the difference between bacterial and mammalian cells in the source of folic acid. Susceptible microorganisms synthesise folic acid, whereas mammalian cells use preformed folic acid.

Trimethoprim selectively inhibits the enzyme dihydrofolate reductase thereby preventing the conversion of dihydrofolic acid into tetrahydrofolic acid, this sequential enzymatic blockage resulting in a synergistic effect and enhanced activity at the site of infection when the two compounds are present.

Thus trimethoprim greatly potentiates the antimicrobial activity of sulphonamides both in vitroand in vivo.

5.2 Pharmacokinetic properties

Following intramammary infusion of one syringe to each infected quarter at three consecutive milkings, peak milk concentrations of trimethoprim (mean level = 4.749 µg/ml) and sulfadiazine (mean level = 20.33 µg/ml) were achieved 6 hours after first infusion.

6. PHARMACEUTICAL PARTICULARS

6.1 List of Excipient(s)

Hydrogenated Castor Oil

Arachis Oil

6.2 Incompatibilities

None Known

6.3 Shelf-Life

Shelf life of the veterinary medicinal product as packaged for sale: 2 years.

6.4 Special Precautions for Storage

Do not store above 25ºC.

6.5 Nature and Composition of Immediate Packaging

Duofast Intramammary Suspension is supplied in a syringe (12 ml capacity) which is composed of a high density polyethylene barrel and a low density polyethylene plunger and end cap, delivering 8g of product. Supplied in cartons of 24 unit-dose syringes

6.6 Special Precautions for the Disposal of Unused Veterinary Medicinal Products or Waste Materials Derived From the Use of Such Products, if appropriate

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

7. NAME OR CORPORATE NAME AND ADDRESS OR REGISTERED PLACE OF BUSINESS OF THE MARKETING AUTHORISATION HOLDER

Norbrook Laboratories Limited

Station Works

Camlough Road

Newry

Co. Down, BT35 6JP

Northern Ireland

8. MARKETING AUTHORISATION NUMBER

Vm02000/4175

9. DATE OF FIRST AUTHORISATION/LAST RENEWAL

Date of First Authorisation: 28 January 1999

10. DATE OF REVISION OF TEXT

July 2010