fusidic acid and betamethasone

Action and Spectrum

Actions and Spectrum: 

Mechanism of Action:  

fusidic acid is an antibiotic that inhibits bacterial protein synthesis. It specifically targets and binds to elongation factor G (EF-G), essential for the translocation step of protein synthesis in bacteria. By binding to EF-G, fusidic acid prevents the release of EF-G from the ribosome, thereby inhibiting protein synthesis and ultimately leading to bacterial cell death. 

betamethasone is a synthetic glucocorticoid belonging to the corticosteroid class. It exerts its effects by binding to cytoplasmic glucocorticoid receptors, which form a receptor-ligand complex that translocates to the nucleus. The complex regulates gene expression inside the nucleus, leading to anti-inflammatory, immunosuppressive, and vasoconstrictive effects. 

Spectrum of Activity:  

fusidic acid is primarily active against Gram-positive bacteria, including Staphylococcus aureus (methicillin-sensitive and methicillin-resistant strains) and Streptococcus species. It is less effective against Gram-negative bacteria due to limited penetration through their outer membrane. 

betamethasone inhibits the production and release of pro-inflammatory cytokines and mediators, such as interleukins and prostaglandins. It also suppresses the migration and activation of inflammatory cells, thus reducing inflammation and immune responses. 

Drug Interaction

Adverse Reaction

Frequency defined 

<1% 

Application site irritation 

Application site vesicles 

Contact dermatitis 

Application site edema 

Application site pain 

Burning sensation on skin 

Erythematous rash 

Black Box Warning

Black box warning: 

None 

Contraindication / Caution

Contraindications/caution: 

Contraindications: 

• Hypersensitivity 
• Systemic fungal infections 

Caution: 

• Long-term Use: Prolonged use of the combined fusidic acid and betamethasone formulation should be avoided unless directed by a healthcare professional.  
• Skin Sensitivity: Some individuals may be more sensitive to the ingredients in the combined formulation.  
• Ocular Use: Caution should be exercised when applying the combined formulation near the eyes or on the eyelids, as it may cause irritation or other adverse effects.  
• Infection Monitoring: When using the combined formulation for skin conditions, it is important to monitor for signs of secondary infection. betamethasone, as a corticosteroid, can suppress the immune response, potentially masking the signs of infection. 

Pregnancy / Lactation

Pregnancy consideration: There was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Lactation: Excretion of the drug in human breast milk is known 

Pregnancy category: 

Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

The pharmacological effects of the combination may include: 

• Antibacterial Activity: fusidic acid targets susceptible Gram-positive bacteria, including Staphylococcus aureus and Streptococcus species. It helps to eliminate or control bacterial infections associated with the skin. 
• Anti-inflammatory Effects: betamethasone possesses potent anti-inflammatory properties. It suppresses the immune response, reduces inflammation, and alleviates symptoms such as redness, swelling, and itching associated with dermatological conditions. 
• Immunomodulatory Effects: betamethasone can modulate the immune response by suppressing the release of pro-inflammatory cytokines and inhibiting the migration and activation of inflammatory cells. This helps to mitigate immune-mediated inflammation in certain skin conditions. 

Pharmacodynamics:  

Combining fusidic acid and betamethasone in a formulation allows for a synergistic effect on certain dermatological conditions. The pharmacodynamic effects of the combination may include: 

• Antibacterial Action: fusidic acid targets susceptible Gram-positive bacteria, helping to eliminate or control bacterial infections associated with the skin. 
• Anti-inflammatory Action: betamethasone reduces inflammation by suppressing the release of pro-inflammatory cytokines and inhibiting the migration and activation of inflammatory cells. This results in a reduction of redness, swelling, and itching associated with dermatological conditions. 
• Synergistic Effects: Combining fusidic acid and betamethasone in a formulation allows for a comprehensive approach, simultaneously addressing bacterial infection and inflammation.  

Pharmacokinetics: 

Absorption 

fusidic acid can be absorbed systemically through various routes, including oral, intravenous, and topical administration. The systemic absorption following topical application is minimal, mainly when applied to intact skin. However, absorption may increase if applied to damaged or inflamed skin. betamethasone can be absorbed systemically through various routes, including topical application. The extent of systemic absorption depends on factors such as formulation, concentration, and skin integrity.  

Distribution 

After absorption, fusidic acid is distributed throughout the body, reaching various tissues and fluids. Once absorbed, betamethasone is distributed throughout the body, including target tissues and organs.  

Metabolism 

fusidic acid undergoes extensive hepatic metabolism, primarily through the cytochrome P450 enzyme system. betamethasone undergoes hepatic metabolism, primarily through the cytochrome P450 enzyme system, resulting in the formation of metabolites.  

Elimination and Excretion 

The metabolites of fusidic acid are primarily excreted via the bile into the feces. A small portion may also be excreted in the urine. The metabolites of betamethasone are excreted primarily via the urine. 

Adminstartion

Administration: 

Topical administration: 

Apply a small coating to the afflicted region; keep it away from the eyes only for topical usage. Don’t bandage or wrap the treated area. After usage, wash your hands. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: fusidic acid and betamethasone 

Why do we use fusidic acid and betamethasone? 

The combined formulation of fusidic acid and betamethasone can be used for various dermatological conditions. Here are some common uses: 

• Eczema: The combined formulation may treat eczema, including atopic dermatitis, nummular eczema, and allergic contact dermatitis. betamethasone reduces inflammation and relieves itching, while fusidic acid provides antibacterial activity against potential secondary infections. 
• Dermatitis: The combination can be used to treat different types of dermatitis, such as seborrheic dermatitis and allergic dermatitis. It helps to reduce inflammation, redness, and itching associated with these conditions. 
• Infected Dermatoses: The combined formulation is effective in managing dermatoses that are complicated by bacterial infections. fusidic acid targets and helps eliminate susceptible bacteria, while betamethasone reduces inflammation and supports healing. 
• Intertrigo: Intertrigo is a common skin condition characterized by inflammation in skin folds. Combining fusidic acid and betamethasone can help manage intertrigo by reducing inflammation and treating associated bacterial infections. 
• Impetigo: Impetigo is a bacterial skin infection commonly caused by Staphylococcus aureus or Streptococcus pyogenes. The combined formulation can treat impetigo by providing antibacterial activity and reducing inflammation.