Steroids (Corticosteroids) for Myositis

How do steroids work?

Our immune system acts like the body's defence army. In myositis, parts of this immune army become overactive and begin attacking healthy muscle tissue by mistake.

Steroids act like the body's “fire extinguisher”, rapidly reducing inflammation and bringing the disease under control.

In simple terms, steroids:

• Quickly block the production of inflammatory chemicals
• Reduce swelling and inflammation in muscle tissues
• Stop immune cells from rushing into the muscles
• Protect muscles from ongoing damage while slower medicines begin working

Why are steroids important in myositis?

Many families worry about steroids because of their possible side effects. However, when used carefully under medical supervision, with the lowest effective dose and gradual tapering, they are often very safe and extremely effective.

The main goal is to control inflammation quickly and strongly. Most other medicines used in myositis (such as methotrexate or other immune-modifying medicines) take several weeks to start working.

Steroids are therefore often used as a “bridge treatment”—they control disease rapidly while slower medicines begin taking effect. Once these medicines start working, steroid doses are gradually reduced.

Uses

Steroids are used in:

• Myositis
• Arthritis
• Asthma
• Severe allergies
• Many autoimmune diseases

Types of steroids commonly used

There are several steroid medicines available. They work similarly but differ in strength, duration of action, and dosing schedules.

Examples include:

• Prednisolone
• Methylprednisolone (Medrol®)
• Deflazacort

How are steroids taken?

Steroids are usually taken once daily in the morning, because the body naturally produces steroid hormones early in the day.

They may be given as:

• Tablets
• Syrup
• IV injections in the hospital (for severe disease flares)

Common side effects

Many children tolerate steroids well, especially when doses are monitored carefully.

Some common immediate side effects include:

• Increased appetite
• Weight gain
• Excessive sweating
• Trouble sleeping
• Mood changes or irritability
• Rounding of the face ("moon face")
• Mild swelling of the face or feet

Why are regular tests necessary?

When steroids are used for long periods, doctors may monitor blood sugar, blood pressure, growth in children, bone health, and eye health (including cataracts).

Your doctor will give Vitamin D and calcium supplements, as well as anti-acidity drugs when steroids are prescribed to help prevent side effects.

Missed dose

If you miss a dose, take it as soon as you remember on the same day. If you remember the next day, skip the missed dose and continue your usual schedule.

Never stop steroids suddenly. The body needs time to adjust, and suddenly stopping steroids can sometimes be dangerous.

During illness

Contact your healthcare team if the patient develops a high fever or a serious infection requiring hospital admission. Steroid doses sometimes need adjustment during severe illness.

Healthy diet matters

Steroids can increase appetite, blood sugar, and blood pressure. A healthy diet with less processed sugar, less excess salt, and good calcium intake can help reduce side effects.

Vaccines remain important

Each patient is different — always discuss vaccines with your doctor.

• Inactivated vaccines are generally safe
• Flu vaccination is encouraged
• Live vaccines may need to be delayed while on steroids