A fixed-dose combination topical preparation containing Betamethasone (a potent synthetic corticosteroid of the glucocorticoid class) and Gentamicin (an aminoglycoside antibiotic). This combination is primarily used for the treatment of inflammatory dermatoses complicated by secondary bacterial infections. Betamethasone provides potent anti-inflammatory, anti-pruritic, and vasoconstrictive effects, while Gentamicin provides bactericidal action against a broad spectrum of Gram-positive and Gram-negative bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa.
Adult: Apply a thin film to the affected area 1 to 2 times daily. The frequency may be reduced to once daily or on alternate days once control is achieved. Treatment should not exceed 2 weeks continuously without medical review.
Note: 1. Wash and gently dry the affected area. 2. Take a small amount (a fingertip unit is a guide: the amount from the tip of the adult index finger to the first crease covers an area twice the size of an adult flat hand). 3. Apply a thin layer and rub in gently until absorbed. 4. Wash hands after application unless hands are the treatment site. 5. Do not cover with occlusive dressings unless specifically directed by a physician. 6. Do not apply to the face, groin, or axillae unless specifically prescribed for those areas and for a very short duration.
The combination exerts a dual mechanism: 1) Betamethasone binds to cytoplasmic glucocorticoid receptors, modulating gene transcription. This leads to inhibition of phospholipase A2, reducing the production of pro-inflammatory mediators like prostaglandins and leukotrienes. It also suppresses the release of cytokines, inhibits inflammatory cell migration, and causes vasoconstriction. 2) Gentamicin binds irreversibly to the 30S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis and causing misreading of mRNA, leading to bacterial cell death.
Pregnancy: Category C (US FDA). Topical corticosteroids, especially potent ones, should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Avoid large amounts or long-term use. Animal studies show teratogenicity with systemic corticosteroids. Data on topical gentamicin in pregnancy is limited.
Driving: No effect on driving ability.
| Other Topical Corticosteroids | Additive risk of local and systemic side effects. | Major |
| Systemic Corticosteroids (e.g., Prednisolone) | Increased risk of hypercortisolism and adrenal suppression. | Major |
| Other Aminoglycosides (Systemic or Topical, e.g., Neomycin) | Increased risk of ototoxicity and nephrotoxicity. | Moderate |
| Loop Diuretics (e.g., Furosemide) | Potentiates the ototoxic risk of gentamicin. | Moderate |
| Neuromuscular Blocking Agents (e.g., Succinylcholine) | Gentamicin may potentiate neuromuscular blockade, leading to respiratory depression. | Moderate |
Same composition (Betamethasone (NA) + Gentamicin (NA)), different brands: