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Neopen Suspension for injection 100ml


Item no: NEOPEN
Prescription Medicine

Out of stock

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Neopen Suspension for injection 100ml.


Neopen is an off-white suspension of procaine penicillin in a solution of neomycin sulphate.

Each ml contains:

Neomycin base

(as the sulphate)

100 mg

Procaine benzylpenicillin

200 mg (200,000 i.u.)


Penicillin is active against some Gram-negative and most Gram-positive bacteria. Neomycin is a broad spectrum antibiotic active against a number of Gram-positive and Gram-negative bacteria.

For the treatment of infectious diseases in horses, sheep, pigs, dogs and cats caused by bacteria sensitive to the combination. The combination shows a broad spectrum of activity.

In vitro activity has been demonstrated against all tested isolates of Erysipelas rhusiopathiae, Streptococcus spp. and Actinomyces pyogenes and the majority of tested isolates of Pasteurella, Salmonella, Klebsiella and Staphylococcus spp.

Dosage and administration

The following table is only intended as a guide and is calculated at a dosage rate of 5 mg/kg neomycin base (5 ml/100 kg) for large animals and 10 mg/kg (1 ml/10 kg) in small animals as representing the maximum dose.



Maximum dose


500 kg

25.0 ml


50 kg

2.5 ml


50 kg

2.5 ml


10 kg

1.0 ml


5 kg

0.5 ml

The dose should be repeated at 24 hour intervals as required to a maximum of three doses.

Administration should be by deep intramuscular injection in all species. Observe aseptic precautions.

A suitably calibrated syringe should be used to ensure accurate injection of small volumes.

Contra-indications, warnings, etc

Overdosage with neomycin parenterally can cause renal damage and deafness but this is unlikely at normal therapeutic dosage levels. Care should be taken in young animals, particularly puppies, kittens and piglets, to ensure accurate computation of the dose.

Courses of this product should be restricted to a period of three days.

Occasionally in sucking and fattening pigs, administration of this product may cause a transient pyrexia, vomiting, shivering, listlessness and incoordination.

Additionally in pregnant sows and gilts, a vulval discharge which could be associated with abortion has been reported. The balance of risks should be considered carefully prior to use.

Local reaction (swelling) may occur at the injection site in horses for up to a week after administration.

Doses exceeding 15 ml should be divided between two injection sites.

Not to be used in animals known to be hypersensitive to Beta-lactam antibiotics.

Operator warnings

Care should be taken to avoid accidental self-injection.

Penicillins and cephalosporins may cause hypersensitivity (allergy) following injection, inhalation, ingestion or skin contact. Hypersensitivity to penicillins may cause cross reactions to cephalosporins and vice versa. Allergic reactions to these substances may occasionally be serious.

1.Do not handle this product if you know you are sensitised, or if you have been advised not to work with such preparations.

2.Handle this product with great care to avoid exposure, taking all recommended precautions.

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

Wash hands after use.

Withdrawal periods:

Pigs and sheep should not be slaughtered for human consumption during treatment. Pigs may only be slaughtered for human consumption from 60 days after the last treatment; sheep from 70 days after the last treatment.

Not to be used in sheep producing milk for human consumption.

Not to be used 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.


For animal treatment only. Keep out of the reach and sight of children.

Pharmaceutical precautions

Store between +2°C and +8°C. Protect from light.

Keep container in outer carton.

Shake container before use. Following withdrawal of the first dose, use the product within 28 days. When the container is broached for the first time, the date on which any product remaining in the container should be discarded should be calculated. A statement of the in-use shelf life of the product is given on the packaging insert. This discard date should be written in the space provided on the label.

Dispose of any unused product and empty containers in accordance with guidance from your local waste regulation authority.

Legal category


Packaging Quantities

Glass bottles or polyethylene terephthalate (PET) bottles containing 100 ml.


Shipping charges mainland GB zone1

Value Weight Delivery Charge
Over £49.00 Any Weight FREE
Under £49.00 No weight limit £4.50
Under £49.00 Under 250 grams £3.49

Most orders are despatched the same day and standard delivery is 3 to 5 working days from despatch. FAST Expedited options are available at extra cost - these usually arrive in 24-48hrs from dispatch but delays are possible during busy periods.

Postcodes outside of Zone 1 (including some areas within mainland UK) may incur extra carriage charges due to surcharges imposed by the couriers. These will be calculated on the website at the checkout. 

NB: Orders placed with faster delivery must be placed before 13:00 to ensure same day dispatch (excluding weekends and bank holidays). Please also check on the product page that the items ordered show 'In Stock' otherwise your order will be delayed until the stock becomes available, which in most cases will only be 24hrs.

Estimated "Usually shipped in" information is shown against most products

Overseas orders

We no longer send goods outside of the UK.

Prescription Items

Prescription items will be sent on receipt of a legally valid signed and dated prescription.

Pick up

We offer a pickup service for orders placed over the phone.

Please ring us on 01833 641112 for more information.

Refrigerated Items

  • Refrigerated lines Packaging Cost: Despatched with Woolcool Refrigerated Packaging for £7.50.
Wool cool keeps pharmaceutical products at fridge-like, ambient, or even freezing temperatures for up to 72 hours, and possibly longer depending on the contents and use of ice packs.
Important Delivery Information:
  • Receipt Required: Someone must be available to receive the delivery. Woolcool packaging is designed for temperature-controlled goods, so parcels cannot be left unattended.
  • Immediate Refrigeration: Upon receipt, refrigerate the contents immediately to ensure your food or medicine remains at the correct temperature.
  • Failed Delivery Attempts: We are not responsible for the cost of replacements if a delivery attempt fails due to the absence of someone to receive it.

We want you to be completely satisfied with any purchase. If not any item* can be returned to us within 14 days of receipt for exchange or refund Please give us a ring for a returns number on 01833 641112 or alternatively email sales@hyperdrug.co.uk to obtain a returns number.

*Due to legal requirements medicines may not be returned except to correct an error in despatch or in response to an "official recall". If an item is believed to be faulty it should be returned for inspection and it may be necessary to forward it to the manufacturers for testing before replacements or refunds can be authorised. This does not infringe legal rights. Please contact our customer services for a "Returns Number" which must appear on the outside of the package or it will not be accepted. We advise customers to use an insured method of shipping and to retain proof of despatch. We may refuse returns on products specially obtained or manufactured to order. Items must be returned unsoiled and unused and sent adequately packed and carriage paid.

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