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Beclomethasone

For medical students2 min readUpdated 2026-10-10

Beclomethasone is a topical inhaled glucocorticosteroid used in the management of respiratory conditions. It serves as baseline anti-inflammatory therapy for bronchial asthma, offering high local potency and minimal systemic activity.

ClassInhaled glucocorticosteroids (ICS)

FormulationMetered-dose aerosol (1 inhalation = 50 mcg)

Onset of actionGradual, maximum by days 5–7

CautionNot suitable for relieving acute bronchospasm attacks

Mechanism of Action and Pharmacokinetics

The structure of beclomethasone is based on a steroid nucleus (cyclopentanoperhydrophenanthrene). The drug contains a chlorine atom at the 9-alpha position, making it a halogenated steroid with enhanced glucocorticoid activity.

The main challenge with inhaled steroids is the risk of systemic (resorptive) effects. The drug can be cleared from the airways by mucociliary clearance, deposited in the oral cavity, swallowed, and absorbed from the gastrointestinal tract into the bloodstream.

To minimize systemic effects, beclomethasone undergoes intensive presystemic elimination. The fraction of the drug reaching the GI tract is rapidly degraded during its first pass through the liver and does not reach the systemic circulation in an active form. Unlike systemic drugs (prednisolone, dexamethasone), beclomethasone acts topically.

Pharmacological Effects

The drug exerts pronounced anti-inflammatory, anti-allergic, and anti-edematous effects on the airway mucosa.

Reduces eosinophilic infiltration of lung tissue.
Decreases bronchial hyperreactivity.
Improves pulmonary function test (PFT) parameters.
Exerts a permissive effect: restores the sensitivity of bronchial receptors to bronchodilators, which is critical in severe asthma.

Indications

Because the drug's action develops gradually, it is intended exclusively for regular, systematic (maintenance) treatment rather than emergency relief.

Pulmonology: Steroid-dependent bronchial asthma (most severe cases). Administered via aerosol inhalation.
ENT pathology: Vasomotor and allergic rhinitis. Administered intranasally (as nasal sprays).

Adverse Effects and Contraindications

Due to its pharmacokinetic properties, systemic effects are virtually absent. Adverse effects are primarily local in nature:

Voice apparatus: Dysphonia (hoarseness).
Irritant effects: Cough, sneezing, throat irritation, and burning in the throat or larynx.
Infectious complications: Prolonged use may lead to oral candidiasis (oral thrush) of the mouth and upper respiratory tract.
Specific reaction: Paradoxical bronchospasm occurs rarely. Intravenous theophylline is used to relieve it.

Contraindications: Active pulmonary tuberculosis and the first trimester of pregnancy.

Administration and Prescription Writing

The drug is available as metered-dose aerosols (including dose optimizers) and dry powder inhalers (with dosing devices or diskhalers).

Maintenance dose is 100–200 mcg. Frequency is 2–4 times daily.

Prescription example: Rp.: Aeros. Beclomethasoni 0.05 mg - 1 dose D.t.d. N. 1 S. Inhale 2 puffs twice daily.

Mnemonic

BEC-lomethasone = BECause maintenance is key, it has NO quick relief. It works as a BASE (baseline therapy) with a slow onset (max effect in 5–7 days), making it useless during an acute asthma attack.

Frequently asked questions

What is the molecular mechanism of the anti-inflammatory action of beclomethasone?

The molecular mechanism of beclomethasone's anti-inflammatory action involves the inhibition of the enzyme phospholipase A2.

Induction of synthesis — the drug stimulates the production of lipocortin proteins (annexins), specifically lipocortin-1.
Enzyme inhibition — lipocortins block the activity of phospholipase A2, halting the hydrolysis of cell membrane phospholipids.
Substrate depletion — the release of arachidonic acid is prevented.
Blockade of inflammatory pathways — mediator synthesis via the cyclooxygenase (prostaglandins) and lipoxygenase (leukotrienes) pathways is halted.

Additionally, there is repression of genes responsible for the synthesis of pro-inflammatory cytokines.

How can oral candidiasis be prevented when using beclomethasone?

To prevent oral candidiasis when using beclomethasone, patients must rinse their mouth with water after inhalation.

Oral and pharyngeal candidiasis is a local adverse effect of inhaled glucocorticosteroids, including beclomethasone, especially with prolonged use.

What are the contraindications to beclomethasone?

Contraindications to beclomethasone include:

First trimester of pregnancy;
Active pulmonary tuberculosis.

Why doesn't beclomethasone cause severe systemic side effects like prednisolone?

Beclomethasone undergoes high presystemic elimination. The fraction of the dose that is swallowed and absorbed in the GI tract is rapidly degraded during its first pass through the liver, preventing entry into the systemic circulation.

What is the permissive effect of beclomethasone?

It is the drug's ability to restore the sensitivity of bronchial receptors to bronchodilators. Due to this effect, rescue medications start working again in patients with severe asthma.

Why does oral candidiasis develop with beclomethasone inhalation?

This local infectious complication occurs because a fraction of the drug deposits in the oral cavity and pharynx, exerting a local immunosuppressive effect with prolonged use.

How does beclomethasone differ from budesonide and flunisolide?

Beclomethasone is a halogenated steroid (contains chlorine) and is used 2–4 times daily. Budesonide is non-halogenated, acts longer (1–2 times daily), but has a slower onset of effect. Flunisolide has higher absorption into the systemic circulation (bioavailability up to 40%).

Go deeper

Comparative pharmacokinetics of ICS: beclomethasone, budesonide, flunisolide.
Mechanism of paradoxical bronchospasm and the role of theophylline in its management.
Presystemic elimination: physiological basis of the first-pass effect through the liver.
Systemic glucocorticoids (prednisolone, dexamethasone) in the management of severe bronchial asthma.
Mucociliary clearance as a pathway for clearing inhaled drugs.