Pharmacological properties : תכונות פרמקולוגיות

Pharmacodynamic Properties

5.1   Pharmacodynamic Properties
Pharmacotherapeutic group: Opthalmologicals; Other antiallergics, ATC Code: S01GX01.

In vitro and in vivo animal studies have shown that Sodium cromoglicate inhibits the degranulation of sensitised mast cells which occurs after exposure to specific antigens.
Sodium cromoglicate acts by inhibiting the release of histamine and various membrane derived mediators from the mast cell.

Sodium cromoglicate has demonstrated the activity in vitro to inhibit the degranulation of non- sensitised rat mast cells by phospholipase A and subsequent release of chemical mediators.
Sodium cromoglicate did not inhibit the enzymatic activity of released phospholipase A on its specific substrate.

Sodium cromoglicate has no intrinsic vasoconstrictor or antihistamine activity.

Pharmacokinetic Properties

5.2   Pharmacokinetic Properties

Sodium cromoglicate is poorly absorbed. When multiple doses of Sodium cromoglicate ophthalmic solution are instilled into normal rabbit eyes, less than 0.07% of the administered dose of Sodium cromoglicate is absorbed into the systemic circulation (presumably by way of the eye, nasal passages, buccal cavity and gastrointestinal tract). Trace amounts (less than 0.01%) of the Sodium cromoglicate does penetrate into the aqueous humour and clearance from this chamber is virtually complete within 24 hours after treatment is stopped.

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In normal volunteers, analysis of drug excretion indicates that approximately 0.03% of Sodium cromoglicate is absorbed following administration to the eye.