Makindo Medical Notes

Related Subjects: |Beta Antagonists/Blockers |Calcium Channel Blockers |Corticosteroids

Mode of Action

• Steroids, also known as corticosteroids, are synthetic forms of hormones that mimic the effects of natural cortisol produced by the adrenal glands.
• They work by binding to glucocorticoid receptors and modulating the expression of certain genes, leading to anti-inflammatory and immunosuppressive effects.
• Steroids reduce inflammation by decreasing the production of inflammatory mediators, such as cytokines, and inhibiting immune cell activation.

Indications

• Autoimmune Diseases: Used to suppress inflammation in conditions like rheumatoid arthritis, lupus, and multiple sclerosis.
• Allergic Reactions: Effective in treating severe allergic reactions, such as anaphylaxis and angioedema.
• Asthma and COPD: Steroids help reduce airway inflammation and prevent exacerbations in chronic respiratory conditions.
• Adrenal Insufficiency: Used to replace deficient hormones in conditions like Addison's disease.
• Cancer Therapy: Steroids can help reduce inflammation and swelling in certain cancers and improve appetite.

Drug Classification

• Glucocorticoids: Primarily used for their anti-inflammatory and immunosuppressive effects. Common examples include prednisone, dexamethasone, and methylprednisolone.
• Mineralocorticoids: Mainly involved in electrolyte and fluid balance. Example: fludrocortisone, used for adrenal insufficiency.

Delivery Forms

• Oral: Commonly used for chronic conditions like rheumatoid arthritis and asthma. Examples include prednisone and prednisolone.
• Intravenous (IV): Used in acute settings for conditions like anaphylaxis and severe asthma exacerbations. Examples include methylprednisolone and dexamethasone.
• Inhaled: Primarily used in asthma and COPD to deliver medication directly to the lungs. Examples include beclometasone and budesonide.
• Topical: Used for skin conditions like eczema and psoriasis. Examples include hydrocortisone and betamethasone.
• Intramuscular (IM): Provides a slower release and longer effect. Often used for allergy or inflammatory flare-ups.

Side Effects

• Osteoporosis: Long-term steroid use can weaken bones, increasing the risk of fractures.
• Hyperglycemia: Steroids can raise blood glucose levels, potentially leading to or worsening diabetes.
• Weight Gain and Fluid Retention: Common with long-term steroid use due to altered metabolism and fluid retention.
• Immune Suppression: Prolonged use can increase susceptibility to infections.
• Cushingoid Appearance: Long-term use may cause fat redistribution, resulting in "moon face" and "buffalo hump."
• Psychiatric Effects: Mood changes, insomnia, and in some cases, psychosis.

Drug Interactions

• NSAIDs: Concurrent use increases the risk of gastrointestinal bleeding and ulcers.
• Diuretics: May worsen electrolyte imbalances, particularly potassium depletion.
• Diabetes Medications: Steroids can antagonize the effects of insulin and other diabetic medications, leading to higher blood glucose levels.
• Anticoagulants: Steroids may enhance the anticoagulant effect of drugs like warfarin, requiring careful monitoring.

Monitoring and Precautions

• Regular monitoring of blood pressure and blood glucose is essential, especially in patients on long-term steroids.
• Bone density should be assessed periodically, particularly in elderly patients at risk of osteoporosis.
• Patients should be monitored for signs of infection due to immunosuppression.
• Avoid abrupt discontinuation after prolonged use, as this can lead to adrenal insufficiency; taper doses gradually under medical supervision.

Patient Education

• Inform patients of the importance of tapering doses gradually rather than stopping abruptly.
• Advise patients to report any unusual symptoms, such as mood changes, weight gain, or increased thirst and urination.
• Encourage a calcium and vitamin D-rich diet and discuss potential osteoporosis prevention strategies if on long-term therapy.
• Patients should be aware of infection risks and avoid exposure to infections whenever possible.

Common Steroids: Names, Doses, and Indications

Caution should be used in patients with any of the following:

• Tuberculosis, Immunocompromised
• Pregnancy, Active untreated infection
• Sarcoidosis, Sepsis
• Peptic ulcer disease, Diabetes mellitus
• Renal or hepatic dysfunction
• Malignant hypertension

Equivalent anti-inflammatory doses of glucocorticoids

• Prednisolone 5 mg
• Hydrocortisone 20 mg
• Methylprednisolone 4 mg
• Dexamethasone 0.75 mg
• Betamethasone 0.75 mg

Prescribing advice

• Wherever possible local treatment with creams, eye drops, etc, should be used instead of systemic treatment.
• The dosage of steroids varies widely in different diseases and patients. The lowest dose that will produce an acceptable response should be used.
• Patients should be made aware of the potential hazards and should carry a "steroid card" giving details of their therapy and patient information.
• After long-term corticosteroid treatment the dose should be gradually reduced over a period of several weeks or months.
• Patients receiving oral or parenteral steroids for reasons other than replacement are at risk of severe chickenpox unless they have already had the disease.

Exposure to chickenpox or herpes zoster

• Advise patients on steroids other than a replacement to avoid close personal contact with chickenpox or herpes zoster and seek urgent medical attention if they are exposed to it.
• Passive immunisation with varicella-zoster immunoglobulin is needed for exposed non-immune patients receiving systemic corticosteroid or for those who have used them within three months.
• Varicella-zoster immunoglobulin should be given within three days of exposure and no later than ten days
• Normal immunoglobulin may also be given for prophylaxis after exposure to measles in children with compromised immunity and in adults with compromised immunity who have no measles antibodies.