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Ronaxan Tablets for Dogs & Cats

Ronaxan Tablets for Dogs & Cats

  • 20mg » Priced per Tablet £0.69
  • 100mg » Priced per Tablet £1.39

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£0.69 to £1.39


Ronaxan Tablets contain the antibiotic doxycycline and are used in cats and dogs. The spectrum of activity of Ronaxan makes it particularly suitable for respiratory infections and so it is usually used for rhinitis, sinusitis, tonsilitis and broncho-pneumonia. Doxycycline is more fat soluble than many other antibiotics and penetrates tissues well, so it is sometimes prescribed for other infections, such as prostatitis in male dogs. Ronaxan Tablets are normally given once daily with a meal for 5 days.

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Medication Datasheets

100mg » Priced per Tablet

Ronaxan 20mg, 100mg Tablet

Qualitative and quantitative composition

Each tablet contains:

Active substances: Doxycycline 20 mg or 100 mg as doxycycline hyclate.

For the full list of excipients, see below.

Pharmaceutical form

Round, biconvex, light yellow to yellow scored tablet. The tablets can be divided into equal parts.

Clinical particulars

Target species

20 mg tablets are indicated for use in both cats and dogs, 100 mg tablets are indicated for use in dogs only.

Indications for use

Treatment of respiratory tract infections in cats and dogs, including rhinitis, tonsillitis, bronchopneumonia and feline respiratory disease, due to organisms sensitive to doxycycline including: Pasteurella spp., Bordetella bronchiseptica, Staphylococcus aureus and other Staphylococcus spp., and Streptococcus spp.

Treatment of arthropod-borne Ehrlichia canis infection in cats and dogs.


Do not use in pregnant animals. Do not use in known cases of hypersensitivity to the active ingredient. Vomiting, oesophagitis and oesophageal ulcerations have been reported as side effects following doxycycline therapy, and Ronaxan should not therefore be administered to patients with dysphagia or diseases accompanied by vomiting.

Special warnings for each target species

None known.

Special precautions for use in animals

Do not exceed the recommended dosage. Tablets should be administered at feeding time.

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

Wash hands thoroughly after use. Handle the tablets with care if you know you are hypersensitive (allergic) to tetracycline. In case of accidental ingestion, seek medical advice.

Adverse reactions

Photodermatitis has occurred following tetracycline therapy after exposure to intense sunlight or ultraviolet light. Use of tetracycline during the period of tooth development may lead to tooth discolouration. Doxycycline, because of its lower affinity for calcium, carries a lower risk than other tetracyclines. Refer also to section 'Contra-indications'.

Use during pregnancy, lactation or lay

Laboratory studies have not revealed any teratogenic, or embryotoxic effect of doxycycline in the rat and rabbit. However, as there is no information available in the target species, use is not recommended during pregnancy.


Cross resistance to other tetracyclines can occur. Doxycycline should not be used concurrently with other antibiotics especially bactericidal drugs such as the β-lactams. The half-life of doxycycline is reduced by concurrent administration of barbiturates or phenytoin. Simultaneous administration of oral absorbents, iron preparations and antacids should be avoided as they reduce doxycycline availability.

Amounts to be administered and administration route

The tablets are for oral administration. The dosage is 10 mg doxycycline per kilogram of bodyweight (one 20 mg tablet per 2 kg or one 100 mg tablet per 10 kg of bodyweight), administered daily for up to five days. In order to adjust the dosage, the tablets can be divided into two equal parts.

For treatment of infections caused by Ehrlichia canis the dose is 10 mg/kg/day for 28 days. Complete eradication of the pathogen is not always achieved but extended treatment for 28 days leads to a resolution of the clinical signs and a reduction of the bacterial load. Longer duration of treatment, based on a benefit-risk assessment by the responsible veterinarian, may be required in severe and chronic ehrlichiosis. All treated patients should be regularly monitored even after clinical cure.

Tablets should be administered at feeding time.


The toxicity and tolerance studies have shown that this product is very well tolerated in cats after five times the recommended dose. Raised levels of SGPT, GGT, SAP and total bilirubin were noted in dogs which received three or five times the recommended dose. Some vomiting can occur in dogs with five times the recommended dosage.

Pharmacological particulars

Doxycycline is a second generation, broad spectrum cycline belonging to the tetracycline family. ATCvet code: QJ01AA02

Pharmacodynamic properties

It is active against a large number of Gram positive and Gram negative pathogens including strains resistant to first generation tetracyclines. It is essentially bacteriostatic; it inhibits the bacterial protein synthesis by blocking binding of transfer RNA to the messenger RNA-ribosome complex.

Pharmacokinetic properties

After oral administration in dogs and cats at the recommended dose of 10 mg/kg, doxycycline is rapidly absorbed reaching the maximal plasma concentration in about 3 hours (Tmax). The peak concentration (Cmax) is 4.5 μg/ml and 3.8 μg/ml in dogs and cats respectively. The oral bioavailability of doxycycline after repeated administration is approximately 45% in both species, and is not affected by the presence of food. In spite of a high protein binding rate, the volume of distribution of doxycycline is high demonstrating that doxycycline is broadly distributed in organs and tissues. Doxycycline is mainly excreted as unchanged drug and eliminated in faeces and urine. Mean elimination half-life is 7.8 hours in dogs and 5.8 hours in cats

Pharmaceutical particulars


Magnesium Stearate, Microcrystalline Cellulose.

Major incompatibilities

None known.

Shelf life

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

Special precautions for storage

Do not store above 25 °C. Store in a dry place. Protect from light.

Immediate packaging

Packs of 5 blister strips each containing 10 tablets.


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

Marketing Authorisation Number

Vm 08327/4068

Vm 08327/4069

Legal category

Delivery Information

How quickly do you deliver?

Under almost all products on our website is an Estimated dispatch time, check this for a delivery prediction specific to the item you are looking to purchase. These badges are updated live based on the stock levels we have and also those of our suppliers - so are usually very accurate, but cannot be guaranteed. In more general terms, we aim to dispatch all orders within 1 working day of receiving payment (and a prescription if required). If we cannot do so within 3 working days we will contact you by email.

What do you charge for delivery?

For UK delivery, we charge the following:

Order Total Weight Delivery
£0-£28.99 Under 2kg £2.99
2kg+ £4.99
£29-£38.99 Under 2kg Free
2kg+ £4.99
£39+ Under 2kg Free
2kg+ Free

Prices quoted are for delivery to all parts of mainland UK except certain Scottish postcodes (where the price is higher for items sent by courier. Delivery of food abroad (including Channel Islands, N. Ireland and other islands around the UK) is charged at a higher price and free delivery is not available. Temperature controlled products, such as Insulin, are also not always subject to the standard and/or free delivery options.

For full information on our delivery charges, including prices on heavy deliveries to Scotland and abroad, see our delivery information page.

We can deliver most items to all around the world, but prices do vary. The majority of light weight orders (less than 1.5kg) can be delivered for a flat rate of £10. For an accurate estimate of the delivery charge, please put the items you require in your basket and use the "Estimate Delivery" system on the shopping basket page (you only need to enter your country and postal/zip code) for a quick quote. For deliveries to the USA you may need to go to the checkout page and enter your full address to get a quote (as some services need your state in order to quote too). For more information on international deliveries, please see our delivery information page.

Delivery of aerosols

Due to air freight restrictions aerosols cannot ever be sent abroad by Royal Mail. We appreciate your understanding.

Delivery of temperature controlled items

Some products, such as insulin and frozen food, need to be delivered in insulated packaging to prevent them from getting too warm (or too cold) during transit from us to you. Purchasing any of these items in your order will result in a £1.99 charge being added to the total to cover the high cost of the insulated packaging materials. You only pay the £1.99 once per order, regardless of how many temperature controlled items you purchase in that order.

How do I cancel or return an order?

Please call us as soon as possible if you need to amend or cancel an order on 01582 842096. If your order has been processed for dispatch we will be unable to cancel or amend the order. You will however be able to return your product for a full refund*.

To return an item, you must contact us by phone or email to arrange this BEFORE posting any product back to us. We will explain the process at this stage for you.

*For full details on returns, see our terms and conditions page.

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