Betamethasone

From SEHK Wiki

Betamethasone (中文: 倍他米松)is a steroid with anti-inflammatory and immunosuppressant effects. It is used to treat a wide range of inflammatory and autoimmune conditions.

Indications include:

  • Inflammatory bowel disease
  • Asthma
  • Croup in children
  • dermatitis
  • Rheumatoid arthritis

Equivalent anti-inflammatory doses of steroids

Prednisolone 5 mg is equivalent to Betamethasone 750 micrograms
dexamethasone 750 micrograms
hydrocortisone 20 mg
methylprednisolone 4 mg
triamcinolone 4 mg

Betamethasone is available as various compounds:

Betamethasone diproprionate (branded as Diprosone)

Betamethasone sodium phosphate

Betamethasone valerate (Branded as Betnovate)

Drug Names[edit]

Generic Name HA Code 藥物代碼 Classification藥物分類
Betamethasone (valerate) cream 0.1% 15g BETA13 P1S1S3
Betamethasone (valerate) ointment 0.1% 15g BETA09 P1S1S3
Betamethasone (valerate) Scalp Application 0.1% 30ml BETA06 P1S1S3

Mechanism of Action[edit]

Immunosuppression agent,

Steroid replacement agent,

Anti-inflammatory agent

Dosage[edit]

Dosages of steroids vary widely in different diseases and in different patients.

When long-term steroid therapy is used in some chronic diseases, the adverse effects of treatment may be great. To minimize side-effects the maintenance dose should be kept as low as possible.

Steroids are used both topically (by rectum or eye) and systemically (by mouth or intravenously).

Whenever possible local treatment with creams, intra-articular injections, inhalations, eye-drops or enemas should be used in preference to systemic treatment.

The suppressive action of a steroid on cortisol secretion is least when it is given as a single dose in the morning.

Oral usual range 0.5 – 5 mg daily
By intramuscular injection or slow intravenous injection 4 – 20 mg, repeated up to 4 times in 24 hours
Child dosage: by slow intravenous injection:
  • Infants aged up to 1 year: 1mg
  • 1-5 years: 2 mg
  • 6 to 12 years: 4 mg
  • 12 years and older: adult doses

Doses repeated up to 4 times in 24 hours according to response

Side Effects[edit]

Short-term use[edit]

include nausea and feeling tired. More severe side effects include psychiatric problems including euphoria, nightmares, insomnia, irritability, confusion, suicidal thoughts and behavioral disturbances. This may occur in about 5% of people.

Long-term steroid use can lead to:[edit]

Adrenal suppression
Steroid-induced diabetes
Osteoporosis, muscle wasting and weakness which is a danger, particularly in the elderly, as it can result in osteoporotic fractures for example of the hip or vertebrae
Susceptibility to infection
Cushing’s syndrome moon face, striae, and acne
Endocrine side effects menstrual irregularities and amenorrhea, hirsutism, weight gain, hyperlipidemia
Neuropsychiatric side effects aggravation of schizophrenia, aggravation of epilepsy, insomnia, irritability, mood changes
Dermatological effects easy bruising, impaired wound healing, and thinning of skin
Ophthalmic effects glaucoma, corneal or scleral thinning and exacerbation of ophthalmic viral or fungal disease

Side-effects can be minimized by using lowest effective dose for minimum period possible.

Pharmacokinetics[edit]

Betamethasone is readily absorbed from the gastrointestinal tract.

It is also absorbed when given locally or use rectally as an enema.

Steroid is rapidly distributed to all body tissues.

They cross the placenta and may distributed in small amounts into breast milk.

Drug Management[edit]

Monitoring[edit]

  • Elderly (close supervision required particularly on long-term treatment)
  • Frequent monitoring required if history of tuberculosis (or X-ray changes)
  • blood sugar level, blood pressure, mood change,
  • monitoring of the fluid intake and output, and daily weight records may give early warning of fluid retention.
  • Sodium intake may need to be reduced and calcium and potassium supplements may be necessary.
  • Back pain may signify osteoporosis
  • Height should be monitored in children receiving prolonged therapy with inhaled or nasal steroid.

Drug interaction[edit]

Interactions do not generally apply to steroid used for topical action including inhalation, unless specified.

Drugs given with steroid Potential adverse drug interactions
NSAIDs Increased risk of gastro-intestinal bleeding
Rifampicin Accelerate metabolism of steroid so reduce the effects of steroid
Antidiabetics Steroid antagonize hypoglycaemic effect. Requirements of antidiabetics may be increased.
Antiepileptics:
  • Carbamazepine
  • Phenobarbitone
  • phenytoin
Accelerate metabolism of steroid so reduce the effects of steroidd
Antifungals:
  • amphotericin
Increased risk of hypokalaemia
Antivirals:
  • ritonavir
Increase plasma concentration of steroid – increased risk of adrenal suppression


Digoxin Increased risk of hypokalaemia
Diuretics:
  • frusemide
  • hydrochlorothiazide

antagonize diuretic effect, increased risk of hypokalaemia

Oral contraceptive (oestrogens) Increase plasma concentration of steroid
Theophylline Increased risk of hypokalaemia

Caution[edit]

  • Children and adolescents (growth restriction possibly irreversible)
  • Osteoporosis (post-menopausal women at special risk)
  • Recent myocardial infarction, congestive heart failure
  • Glaucoma (including family history)
  • Ocular herpes simplex – risk of corneal perforation
  • Psychiatric disorders (particularly if history of steroid-induced psychosis)
  • Epilepsy
  • Peptic ulcer
  • Hypothyroidism
  • Ulcerative colitis
  • Diverticulitis
  • Thromboembolic disorders
  • Myasthenia gravis

Contraindication:

  • acute infections
  • patients with active or doubtfully quiescent tuberculosis
  • concurrent treatment live virus vaccines for at least 3 months afterwards

Hepatic impairment[edit]

When steroids are administered orally or parenterally, the plasma-drug concentration may be increased in patients with hepatic impairment. The patient should be monitored closely.

Renal impairment[edit]

Should be used with caution in patients with renal impairment.

Pregnancy[edit]

Betamethasone should only be used in pregnant women when benefits outweigh the risks.

  • No convincing evidence that systemic steroids increase the incidence of congenital abnormalities such as cleft palate or lip.
  • Prolonged use increases the risk of intra-uterine growth; but no evidence of intra-uterine growth restriction following short-term treatment.

Note[edit]

Prolonged use of steroid Recommendation
Immunosuppression

Prolonged use can increase susceptibility to infection

Avoid contact with people who have chickenpox, shingles, or measles.
Adrenal suppression

Steroid suppresses the endogenous secretion of corticotropin by the anterior pituitary, resulting the adrenal cortex becomes atrophied. If given for more than 3 weeks, treatment must not be stopped gradually.

Patient must mention the course of steroid when receiving treatment for intercurrent illnesses or trauma such as surgery.

FAQ[edit]

How should I take the tablet?[edit]

Follow all directions on your prescription label. Use prednisolone exactly as directed on the label. Steroids are associated with a risk of GI irritation. The tablet MUST be with or after food to help reduce side-effects.

What should I avoid while taking?[edit]

Avoid abruptly discontinue the medication. Should not be taken with NSAIDs.

What happen if I overdose?[edit]

Contact your primary care doctor. If emergency situation, call 999

What happen if I miss a dose?[edit]

Take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.