Beclomethasone

Chemical

Synthetic glucocorticoid

Use

Asthma prophylaxis

Presentation

Aerosol metered suspension

Dose

800mcg OD max (inhaled)

42mcg/spray

8.0mcg/spray 

MoA

  • Glucocorticoid receptor AGONIST
  • Binds corticoreceptor-ligand complex
  • Translocates itself into cell nucleus
  • Alters protein DNA transcription
  • Inhibits phospholipase A2 (which breaks down phospholipids to give Arach. Acid)
  • ↓PG/leukotriene/IL production
  • ↓inflam cascade, ↓oedema, ↓capillary leakiness
  • ↓airway hyperresponsiveness

PD

Resp: ↓airway inflammation + ↓airway hyperresponsiveness

PK

A

10% dose deposited to resp tract

Rest is deposited to mouth/oesopharynx

→ Absorbed

→ systemic effects usually do not occur due to rapid liver metabolism

D

87% PPB

M

Esterase enzymes → rapid + extensive conversion to 17BMP

Most metabolised rapidly by liver

E

Faeces

t ½ 3hrs

Adverse Effects

  • V. low, unlikely
  • Large dose will suppress HPA axis