Corticosteroids - Medicines that interact with corticosteroids

Corticosteroids can interact with other medicines and the effects of one of the medicines can be altered. This is known as drug-drug interaction.

There is less chance of interaction with corticosteroid injections or sprays, although they can occasionally occur.

Interactions with other medicines

Some of the more common interactions are listed below, but this is not a complete list. If you want to check your medicines are safe to take with corticosteroids, ask your GP or pharmacist, or read the patient information leaflet that comes with your medicine.

Anticoagulant medicines

Anticoagulant medicines are medications that make the blood less sticky. They are often prescribed to people with a history of blood clots or an increased risk of developing them.

Combining corticosteroids with anticoagulant medicines can sometimes make anticoagulants less effective. Alternatively, it can increase their blood-thinning effect, which can cause bleeding inside the digestive system.

Anticonvulsants

Anticonvulsants are medicines used to prevent seizures (fits) and are often used to treat epilepsy. However, they can reduce the effectiveness of corticosteroids. Depending on how frequent and severe your seizures are and the condition that the corticosteroids are being used to treat, your course of anticonvulsants may be temporarily withdrawn.

Anti-diabetes medication

Corticosteroids, particularly steroid tablets (oral corticosteroids), can decrease the effectiveness of medications used to treat diabetes. If you need to take both medications, it is recommended that your blood glucose levels are regularly checked because your dosage of anti-diabetic medication may need to be adjusted.

Antiretroviral medication

Inhaled or intranasal corticosteroids can interact with a type of antiretroviral medication known as protease inhibitors. For example, ritonavir, used to treat HIV and AIDS.

This could lead to side effects such as Cushing's syndrome, high blood pressure and osteoporosis.

Bronchodilators 

Bronchodilators are medicines that open up the small airways of the lungs (bronchi) to make breathing easier. They are often used to treat conditions that can cause the airways to become narrow or inflamed such as:

• asthma 
• bronchiectasis – a lung condition where the airways are abnormally widened
• chronic obstructive pulmonary disease (COPD) – permanent damage to the lungs usually caused by smoking

Combining corticosteroids and bronchodilators can sometimes cause a fall in levels of potassium in the body. This can lead to abnormal heart rhythms. If you need to take both types of medication, regular blood tests to measure your potassium levels may be recommended.

Live vaccines

Some vaccinations contain a weakened form of the infection they are designed to protect against. These are known as live vaccines. Examples of live vaccines include:

• measles, mumps and rubella (MMR) vaccine
• bacillus Calmette-Guérin (bCG) vaccine for tuberculosis

Due to the immune-weakening effects of corticosteroids, you should postpone any vaccination with a live vaccine for at least thee months after your course of corticosteroids has finished.

Non-steroidal anti-inflammatory drugs

Non-steroidal anti-inflammatory drugs (NSAIDs) are a group of commonly used painkillers, such as ibuprofen, that are available over the counter at pharmacists.

Combining NSAIDs and corticosteroids can increase your risk of developing stomach ulcers and internal bleeding. Depending on other risk factors, you may be given an additional medication called a proton pump inhibitor (PPI). PPIs help reduce the production of stomach acids, which can lower the risk of ulcers forming.