Researchers have identified a “dose response risk” between steroids and infection, meaning that the higher the prescribed dose, the more likely it is that corticosteroids may increase the risk of infections. The dosage of the drug has a great impact on the risk of infection, with higher doses (e.g. 60 mg of prednisone) increasing the risk of serious infection twofold. Even doses as low as 10-20 mg of prednisone can increase the risk of infection, though the exact risk is unclear.
Steroids reduce the activity of the immune system, which is the body's natural defense against diseases and infections. Generally, there are no serious side effects if you take steroid injections, a steroid inhaler, or a short course of steroid tablets. However, long-term treatment at high doses can cause problems in some people. For most people, steroid inhalers and steroid injections shouldn't cause annoying side effects.
Steroid tablets are generally prescribed with more caution, as they can cause more problems. Corticosteroid tablets are the most potent type of steroid medication because they can affect the entire body. For example, steroid tablets may be recommended if you are pregnant and have severe asthma, because your baby's risk of uncontrolled asthma is greater than that of the medication. If a woman needs to take steroid tablets while breastfeeding, a type called prednisolone is generally recommended, since it is believed to have the lowest chance of causing adverse effects to the baby.
As a precautionary measure, it is generally recommended that a nursing mother wait three to four hours after taking a tablet before feeding her baby. High-dose inhaled steroids can sometimes cause some of the more serious side effects that are most commonly related to steroid tablets (see below), but this is rare. Short, occasional cycles of steroid tablets taken for no longer than three weeks are highly unlikely to cause annoying side effects.You may have regular checkups and tests for conditions such as diabetes, high blood pressure and glaucoma if you need to take long-term steroid tablets. There's usually no reason why a person can't use a steroid inhaler or spray, but they should be used with caution in people with ongoing infections, such as tuberculosis (TB).
A Danish study found a high risk of diabetes and osteoporosis among patients who had received one or more steroid injections per year for three or more years to treat allergic rhinitis.In conclusion, steroids can increase the risk of infection in certain cases. The dosage and type of steroids used will determine how likely it is that an infection will worsen due to their use. It is important to consult with your doctor before taking any form of steroids to ensure that you understand all potential risks.