Upper and lower respiratory disease is common in rats. Respiratory disease can include a number of signs including sneezing, wheezing, nasal discharge, and unusual noises while breathing.

What causes respiratory disease?

Commonly the cause is a combination of factors, including bacterial, viral, Mycoplasma, stress or environment. Mycoplasma is in almost all chronic respiratory disease in rats, and it can be transferred via aerosolisation, when rats breathe or sneeze on each other, or from the female rat to her babies. Mycoplasma can be normal in the respiratory tract, however if your rat becomes stressed or exposed to another respiratory disease, this can trigger Mycoplasma to show signs. The environment that your rat lives in is also a factor, as ammonia building up in a rat’s cage can destroy cilia inside their respiratory tract. Cilia are small projections extending off the lining of the respiratory tract. Mucous traps dust, dirt or bacteria trying to enter the respiratory tract and the cilia move it back out. Ammonia can destroy these cilia which then allows bacteria to enter the respiratory tract. For this reason we recommend well -ventilated cages with wire walls, rather than glass aquariums to house rats. We also recommend regular and thorough cleaning of rat cages and even litter training your rats.

How do we treat respiratory disease?

Treatment of respiratory disease is aimed at control rather than a cure. Unfortunately in rats when respiratory disease occurs it is usually present for life. Respiratory signs can clear up with the right treatment however in many cases they will recur, as the organisms causing the infection can be very difficult to eliminate from the respiratory tract.

We use a combination of drugs in order to achieve the best relief for rats. These include:


Antibiotics are used to control secondary bacterial infections. Some antibiotics that are prescribed can also have antiinflammatory effects, which will further help relieve symptoms.


Anti-inflammatory drugs are used to control any inflammation that may be occurring in your rat’s airway. This is common in early disease.


Bronchodilators dilate the airways within your rat’s lungs, allowing more air to flow through.


Using a specialised nebuliser which turns drugs into a vapour, medications can be directly delivered to the airways. It is also used to help remove mucous that can build up in airways.

What does it mean if there is red discharge around my rat’s nose or eyes?

This red discharge is called porphyrin and while it looks like blood it is not. Porphyrin secretion occurs in rats due to stress, which is common in rats with respiratory disease.

What else can I do to help my rat?

Your rat will benefit from some extra TLC, including lots of warm bedding such as polar fleece, warm food and plenty of water. If your rat lives outside consider bringing it inside, especially during the cold winter months, as cold weather can exacerbate respiratory disease. Covering their cage with a blanket to reduce draughts and consider providing them with a heat pack, but bear in mind that rats like to nibble! If you are using sawdust as a substrate in your rat’s cage try switching to something less dusty, such as shredded paper, which is less likely to irritate your rat’s airway.