Corticosteroids are a powerful and effective drug that widely used today in many fields of medicine  with injections, inhalers, sprays, pills and ointments.
In some cases, such as of severe asthma, life-threatening allergy, sepsis,  cerebral edema or cancer , it is a life-saving drug ; while in other cases such as psoriasis, arthritis, non-life-threatening asthma, atopic dermatitis, Crohn's, liver and kidney diseases ,it improves short-term quality of life. 
In addition, corticosteroids are found in the human body naturally. It is a component that is not foreign to the body.
So why not simply use steroids in chronic diseases? The answer consists of the following reasons:
1. The side effects of the drug are scanty and can be severe or irreversible in the long run .
2. The drug works by suppressing the immune system and leaves the body exposed and vulnerable to the new diseases .
3. The drug does not solve the source of the problem but only reduces the symptoms so that in many cases the symptoms reappear after stopping the drug .
4. The drug inhibits the body's natural healing process .
For example, injecting corticosteroids into a sore and swollen joint will reduce the swelling and pain but will interfere with the joint healing itself. It is very likely that arthritis will returns after a few months and may even worsen.
In many cases, the attending physician replaces corticosteroids with chemotherapy or biological therapy that have fewer side effects, but even with these treatments, today, there are still similar problems.
For these reasons the use of corticosteroids should be limited, compatible with the severity of the disease. Prolonged use may do more harm than good.
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