bacitracin, neomycin, polymyxin B, and hydrocortisone topical

Action and Spectrum

Mechanism of action

• bacitracin is a polypeptide antibiotic that works by inhibiting the production of bacterial cell wall peptidoglycans
• neomycin is an aminoglycoside antibiotic that works by inhibiting bacterial protein synthesis
• polymyxin B is a cationic polypeptide antibiotic that works by disrupting the integrity of the bacterial cell membrane
• hydrocortisone is a steroid hormone that has anti-inflammatory and antipruritic properties. It works by suppressing the immune response and reducing the production of inflammatory mediators

Spectrum

• bacitracin has a narrow spectrum of activity and is effective against gram-positive bacteria, including Staphylococcus and Streptococcus species
• neomycin has a broad spectrum of activity and is effective against gram-negative bacteria, including Escherichia coli and Klebsiella pneumoniae
• polymyxin B has a narrow spectrum of activity and is effective against gram-negative bacteria, including Pseudomonas aeruginosa
• The topical combination of these antibiotics and hydrocortisone treats infected dermatitis. The antibiotics target the infection, while the hydrocortisone reduces inflammation and itching

Drug Interaction

Adverse Reaction

Frequency undefined:

Burning

Irritation

Folliculitis

Acneiform eruptions

perioral dermatitis

skin macerations

skin atrophy

skin sensitization

itching

dryness

hypertrichosis

hypopigmentation

allergic contact dermatitis

secondary infection

striae

Black Box Warning

Contraindication / Caution

Contraindications

• Hypersensitivity to any of the components of the topical preparation
• Widespread skin infections or open wounds
• Tuberculosis, fungal or viral infections of the skin

Caution

• Prolonged use of topical steroids may result in skin atrophy, striae, and increased susceptibility to infections
• Avoid contact with the eyes and mucous membranes
• Systemic absorption of neomycin and polymyxin B can lead to nephrotoxicity and ototoxicity
• Patients with a history of sensitivity to any aminoglycoside antibiotic should use neomycin cautiously

Pregnancy / Lactation

Pregnancy consideration: Insufficient data available

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

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 available 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

• bacitracin: Inhibits bacterial cell wall synthesis by preventing the incorporation of mucopeptides into the growing cell wall
• hydrocortisone: Antipruritic/anti-inflammatory action with mild-to-medium corticosteroid potency
• neomycin: Bacteriostatic when administered topically
• polymyxin: Bactericidal; causes leakage of the bacterial membrane by binding to phospholipids

Pharmacodynamics

• bacitracin: bacitracin is a polypeptide antibiotic that inhibits bacterial cell wall synthesis. It prevents the incorporation of mucopeptides into the growing cell wall, leading to bacterial cell death. Bacitracin is bactericidal against a narrow range of gram-positive bacteria, including Staphylococcus and Streptococcus species
• neomycin: neomycin is an aminoglycoside antibiotic that inhibits bacterial protein synthesis. It is bacteriostatic against a broad range of gram-negative bacteria, including Escherichia coli and Klebsiella pneumoniae
• polymyxin B: polymyxin B is a cationic polypeptide antibiotic that is bactericidal against a narrow range of gram-negative bacteria, including Pseudomonas aeruginosa. polymyxin B disrupts the integrity of the bacterial cell membrane, leading to bacterial cell death
• hydrocortisone: hydrocortisone is a steroid hormone with anti-inflammatory and antipruritic properties. It works by suppressing the immune response and reducing the production of inflammatory mediators. This results in decreased inflammation and itching in the affected area

In summary, the pharmacodynamics of these topical preparations involve the inhibition of bacterial growth and the reduction of inflammation and itching in the affected area.

Pharmacokinetics

• Absorption: The drug is minimally absorbed through the skin, and systemic exposure is generally considered low
• Distribution: Not much data is available
• Metabolism: Most of the drug is metabolized in the liver
• Elimination/excretion: The drug is excreted through the kidneys

Adminstartion

Administration

It is typically administered as ointments and creams. If necessary, they are applied to the affected skin area and may be covered with a bandage or dressing. The frequency of application and duration of therapy will vary depending on the specific preparation, indication, and severity of the condition being treated.

It is essential to follow the dosing instructions provided by your healthcare provider and avoid using more medication than recommended. In general, it is recommended to apply these topical preparations to intact skin and to avoid using them on large areas of the body for extended periods, as this may increase the risk of systemic effects

Patient Information Leaflet

Patient information leaflet

Generic Name: bacitracin, neomycin, polymyxin B, and hydrocortisone topical

Pronounced: [ bas-i-TRAY-sin, nee-oh-MYE-sin, pol-i-MIKS-in-bee, & hye-droe-KOR-ti-sone ]

Why do we use bacitracin, neomycin, polymyxin B, and hydrocortisone topical?

It is used for the treatment of skin infections and skin conditions that are characterized by itching, redness, and swelling.