DRUGS USED FOR ASTHMA

Drugs

Dosage

MOA

ADR

USES

Sympathomimetic

• Short acting (2- 4 hrs.): Salbutamol (Albuterol), Terbutaline
• Long acting (12 hrs.): Salmeterol- more selective an lipohilic so long duration of action, Formoterol

• Tolbutami de- 0.5-1 gm TDS
• Glibencla mide- 5-20 mg OD or BD

• Cause bronchodilation through ß2 receptor stimulation -> increased cAMP formation in bronchial smooth muscle cell -> relaxation

• Highly selective ß2 receptor agonist
• Cardiac side effects less prominent- Adrenaline, isoprenaline though are effective bronchodilator not used because has cardiac side effect
• Selectivity further increased by inhaling drugs
• Muscle tremor
• Palpitaton
• Restlessness
• Nervousness
• Weakness
• Throat irritation
• Edema
• Hypokalemia

• Bronchial Asthma
• Hyperkalemic periodic paralysis
• COPD- exacerbation
• To delay delivery in premature labor

Contraindicated In

• Cardiac tachyarrhythmia
• Hypertensives
• Ischemic heart disease
• Patient receiving digitalis
• Narrow angle glaucoma

Theophylline

• 500

mg tablet up to 8

tablet per day

• 850

mg BD

Three distinct cellular actions of methylxanthines have been defined-

• Release of Calcium ion from SR, especially in skeletal and cardiac muscles
• Inhibition of phosphodiesterase (PDE) which degrades cyclic nucleotides intracellularly.
• Blockade of adenosine receptors: adenosine act as local mediator in CNS, CVS- contracts smooth muscle (bronchial), dilates cerebral vessels, depresses cardiac pacemaker and inhibit

gastric secretions

• Theophylline has a narrow margin of safety, dose dependent side effects start from upper part of therapeutic concentration (5-20 µg/ml)
• Minimal side effects
• Dyspepsia, headache, nausea, vomiting
• Nervousness, restlessness, tremors, palpitation, diuresis
• Agitation, tachypnea, flushing, hypotension
• Delirium, hypertonia, extra systole
• Convulsion, shock, arrhythmias- due to adenosine A1 receptor antagonism
• Death

• Bronchial asthma
• COPD
• Apnea in premature infants
• Cardiac asthma
• Diuretics
• Heart failure
• COPD
• CO2 narcosis
• Cardiopulmonar y resuscitation
• Cheyne’s stokes

respiration

Anticholinergic

• Ipratropium bromide- short acting (4-6 hrs.)
• Tiotropium bromide– long acting (24 hrs.)



• Atropinic drugs cause bronchodilation by blocking M3 receptor mediated cholinergic constrictor tone; act primarily on larger airways which receive vagal innervation.
• Presence of M3 receptor on peripheral bronchiolar muscle as well, though they do not have vagal innervation.

• Similar to atropine

• Severe asthma
• COPD exacerbation
• Smoker asthmatics
• Perennial rhinitis, watery rhinorrhea

Inhaled corticosteroids



• Anti-inflammatory
• Anti-allergic
• See steroid

Due to inhalation: Hoarseness of voice, dysphonia, sore throat, oropharyngeal candidiasis; can be minimized by using spacer, gargling after every dose; treated by topical nystatin/ clotrimazole

Systemic S/E: only at dose >600 µg/day- see Steroid

• Asthma