Steroids Flashcards
What are corticosteroids?
They are synthetic (man-made) versions of hormones made by adrenal glands. Two Types:
- ALDOSTERONE (Mineralcorticoid
- CORTISOL (Glucocorticoid)
Different corticosteroids have different levels of mineralcorticoid and glucocorticoid activity.
e.g Dexamethasone has great glucocorticoid activity but minimal mineralcorticoid activity.
Corticosteroid indications
Prednisolone commonly used for:
Asthma, COPD, IBD, Eczema
Dexamethasone commonly used for:
Palliative care such as raised intracranial pressure, anorexia
Mineralocorticoid side effects
As corticosteroids mimic the effects of naturally occuring glucocorticoid (CORTSOL) and mineralocorticoid (ALDOSTERONE). However when too much corticosteroids are taken, it can exaggerate these effects and cause glucocorticoid and mineralocorticoid side-effects. Mainly associated with high-doses/long term use
Mineralocorticoid side effects:
Na+ and fluid retention: Hypertension & Oedema
K+ excretion: Hypokalaemia
Fludrocortisone has great mineralocorticoid activity but little glucocorticoid, therefore has little anti-inflammatory properties. Used in conditons where fluid retention is beneficial, such as postural hypotension or shock, which are characterised by low blood pressure.
Hydrocortisone has significant mineralocorticoid activity and moderate glucocorticoid anti-inflammatory activity. Hydrocortisone is unsuitable long term as it will cause fluid retention. Used short term for acute hypersensitivity such as for asthma or anaphylactic reactions.
Glucocorticoid drug activity
Dexamethasone & Betamethasone have the glucocorticoid activity, thus have the most potent anti-inflammatory effects (and minimal mineralocorticoid activity). Beneficial for patients that require greater anti-inflammation, e.g in heart, kidney or liver failure.
Prednisolone has significant glucocorticoid acitivity and minimal mineralocorticoid activity.
Methylprednisolone, Deflazacort are prednisolone derivatives and have similar activity to prednisolone
Corticosteroid side effects - Endocrine
ENDOCRINE
- Cushing’s syndrome - Resulting from high cortisol over a prolonged period
- Raises blood glucose - Hyperglycaemia and diabetes
- controlling fat - Weight gain
ACHING BOSOM
Corticosteroid side effects - Muscoskeletal
MUSCULOSKELETAL
* muscle and bone metabolism - muscle wasting. Potential interaction with a statin due to this, as statins cause myopathy. Can also cause osteoperosis, have to prescribe a bisphosphonate to prevent this.
- Supresses growth in children. Have to monitor their height and weight
ACHING BOSOM
Corticosteroid side effects - gastrointestinal
GASTRO-INTESTINAL
* Peptic ulcers
* Gastro-intestinal irritation
Counsel patients to take steroids with or after food
ACHING BOSOM
Corticosteroid side effects - central nervous system
CENTRAL NERVOUS SYSTEM
* influencing mood/behaiviour and sleep-wake cycle
* Psychiatric reactions through irritability, confusion and delusions. Suicidal thoughts and depression must be reported
* Insomnia - as steroids mimic cortisol. Patients should take dose in the morning and not at night
ACHING BOSOM
Corticosteroid side effects - skin and eye
SKIN
* Skin thinning -
* Purple-red stiae
* Easily bruising
EYE
* glaucoma
* cataracts
Patients MUST report blurred vision and visual disturbance as this may be a sign of central serous chorioretinopathy (acummulation of fluid behind the retina)
ACHING BOSOM
Corticosteroid side effects - immunity and hormones
IMMUNSE RESPONSE
Corticosteroids dampen the immune system, long term use may cause immunosupression. The immune system’s response is suppressed. Increasing the risk of infections and severity. These patients cannot have live vaccines, must be passively immunised.
Patients must avoid contact with measles (and chickenpox and measles if they have not had it before).
+ Applies to patients who have stopped taking corticosteroids within the last 3 months.
ADRENAL SUPPRESSON
When the adrenal glands stop making the body’s natural steroid hormones. As CORTICOsteroids induce negative feedback, so the body makes less of the natural steroid.
Patients on the corticosteroids for over 3 weeks SHOULD NOT abruptly stop, as the body is now dependent on the drug and making less/none of the natural hormone. Suddenly stopping can lead to acute adrenal insufficiency/adrenal crisis, where steroid levels are dangerously low. This is an emergency.
Patients taking long term corticosteroids, do not experience a rise in cortisol as a result of adrenal supression. Any signicant intercurrent surgery or trauma, temporarily requires a higher dose of corticosteroids (even if recently stopped) to meet the increased demand for cortisol
This effect can last up to a year or more after corticosteroids are stopped.
ACHING BOSOM
Corticosteroid sick day rules
During an illness with a fever, glucocorticoid dose needs to be increased.
If patient vomits once, an extra dose can be taken. If it persists, patient needs to go to hospital.
Patients physically dependent on steroids must carry the card, to indicate to HCP that steroids must be administered to mitigate adrenal crisis
Corticosteroid side effects
(summary)
A - adrenal suppression + abrupt withdrawal
C - cushing’s syndrome + cataracts
H - hyerpglycaemia (diabetes), hyerlipidaemia
I - infections + insomnia
N - nervous system + psychiatric reactions
G - glaucoma + gastrointestinal ulcers
B - Blood pressure raised, Oedema, HypOK
O - Osteoperosis
S - skin thinning
O - obesity
M - muscle wasting
Corticosteroid side effects management
- Lowest effective dose for the shortest period
- Take single dose in the morning as cortisol levels are naturally higher in the morning
- To reduce adrenal suppression, can administer a 2-day dose on alternate days and have intermittent short courses
- Use local route INSTEAD OF systemic route
- Patients should carry a steroid card if taking a systemic steroid for over 3 weeks or an inhaler
When can corticosteroids be withdrawn
- If theres been over 3 weeks of use
- If greater than 40mg is taken daily or equivalent for more than 1 week
- If there are repeat doses in the evening
- If its a repeated course
- If the patient is taken a short course, within less than 1 year of stopping corticosteroids
- If there are other causes of adrenal supression such as Addison’s disease
Corticosteroids interactions
- Corticosteroids are metabolised by cytochrome P450 enzymes, therefore taking cytochrome P450 inhibitors (clarithromycin, itraconazole, ketoconazole), increases the conc of corticosteroids in the blood = toxicity
- Corticosteroids are metabolised by cytochrome P450 enzymes, therefore taking cytochrome P450 inducers (carbamazepine, phenutoin, rifampicin) will reduce the conc of corticosteroids in the blood =subtherapeutic effect
- Corticosteroids AND NSAIDs combined will increase the risk of GI bleeding
- Drugs that further increase the existing risk of hypokalaemia (b2 agonst: salbutamol, loop & thiazide diuretic, theophylline, digoxin toxicity, antipsychituc, anti-arrhythmic, Clomipramine (TCA), Clarithromycin and Erythromycin, Citalopram, Escitalopram.
Hypokalaemia predisposes to digoxin toxicity. Hypokalamia is a risk factor for prolonged QT interval.
