Genticin HC0.3%+1%

Genticin HC is indicated for short-term topical or otic use in the following conditions:

Established uses

• Secondarily infected inflammatory skin conditions caused by susceptible bacteria (e.g., infected eczema, infected dermatitis, infected insect bites, and other superficial skin infections with an inflammatory component), applied as the cream or ointment.
• Acute diffuse otitis externa with inflammation caused by susceptible bacteria, in patients with an intact tympanic membrane, applied as ear drops.

Adjunct use

• The corticosteroid component of Genticin HC is used adjunctively with the antibiotic component to relieve the itching, redness, and swelling that accompany the bacterial infection; it is not intended as monotherapy for infection.

Genticin HC should only be used when there is a demonstrated or strongly suspected bacterial component; it is not effective against purely viral or fungal skin/ear conditions and is not recommended for use in or around the eyes.

Each gram of Gentamicin + Hydrocortisone Acetate cream/ointment typically contains gentamicin (as sulfate) 0.3% w/w and hydrocortisone acetate 1% w/w. An otic (ear drop) form of Gentamicin + Hydrocortisone Acetate contains the same strengths of each active ingredient per mL, together with pharmaceutically acceptable excipients suitable for topical or aural use.

Genticin HC is a fixed-dose combination of an aminoglycoside antibiotic and a corticosteroid, formulated as a topical cream/ointment or as ear (otic) drops. It is used for short-term treatment of secondarily infected inflammatory skin conditions and for bacterial otitis externa accompanied by inflammation, where the antibacterial action controls susceptible bacteria while the corticosteroid reduces the associated inflammation, itching, and discomfort.

Genticin HC belongs to the topical/otic antibiotic–corticosteroid combination class (aminoglycoside antibiotic plus glucocorticoid).

Gentamicin + Hydrocortisone Acetate combines two complementary actions:

• The antibiotic component binds irreversibly to the 30S ribosomal subunit of susceptible bacteria, causing misreading of mRNA and inhibition of protein synthesis, producing a bactericidal effect against many Gram-negative organisms (including Pseudomonas aeruginosa, Proteus species, and Escherichia coli) and some Gram-positive organisms, notably Staphylococcus aureus.
• The corticosteroid component reduces local inflammation, erythema, itching, and oedema by inhibiting phospholipase A2, decreasing release of arachidonic acid derivatives (prostaglandins, leukotrienes), and suppressing the local inflammatory and immune response.

When Gentamicin + Hydrocortisone Acetate is applied topically or into the ear canal, systemic absorption of both components is normally minimal through intact skin or an intact tympanic membrane, but can increase significantly with prolonged use, application to large or broken skin areas, use under occlusive dressings, or when the tympanic membrane is perforated.

For skin application: Clean and dry the affected area before applying a thin layer of Genticin HC cream/ointment; gently rub in. Wash hands after application unless the hands are the area being treated. Do not cover with an airtight (occlusive) dressing unless directed by a physician.

For ear application: Warm the bottle briefly in the hand before use. Tilt the head to the side or lie down with the affected ear upward, instil the prescribed number of drops of Genticin HC, and keep the head tilted (or gently pull the earlobe) for a minute or two to allow the drops to reach the ear canal. Avoid touching the dropper tip to the ear to prevent contamination.

Genticin HC is for topical and otic use only; it must not be taken orally, injected, or applied to the eyes.

Genticin HC has limited systemic absorption when used on intact skin or an intact ear canal, so clinically significant drug interactions are uncommon; however, the following should be considered:

• Other ototoxic or nephrotoxic drugs (e.g., systemic aminoglycosides, loop diuretics): concurrent use may increase the risk of ototoxicity or nephrotoxicity if significant systemic absorption of Genticin HC's antibiotic component occurs (e.g., with extensive application, broken skin, or a perforated eardrum).
• Other topical or systemic corticosteroids: concurrent use over the same area or systemically may increase the risk of skin atrophy and hypothalamic-pituitary-adrenal (HPA) axis suppression.
• Live vaccines: significant systemic corticosteroid absorption (unlikely with normal topical/otic use of Genticin HC) could theoretically reduce immune response to live vaccines.

Local reactions to Genticin HC are most common; systemic effects are rare and generally occur only with prolonged or extensive use.

Common

• Local burning, stinging, itching, or redness at the application site
• Dryness or mild irritation of the skin or ear canal

Less common / with prolonged use

• Skin thinning (atrophy), striae, telangiectasia, or delayed wound healing at the application site
• Contact hypersensitivity/allergic dermatitis
• Secondary infection with resistant bacteria or fungi (superinfection)

Rare (usually with prolonged/extensive use or absorption through broken skin or a perforated eardrum)

• Ototoxicity (hearing loss, tinnitus, vertigo)
• Nephrotoxicity
• Hypothalamic-pituitary-adrenal (HPA) axis suppression, particularly in children or with use under occlusion

Data on the use of Genticin HC in pregnancy and lactation are limited. Systemic absorption from topical or otic use is normally minimal, but caution is still advised because systemically absorbed aminoglycosides can cross the placenta and have been associated with fetal ototoxicity, and systemic corticosteroids carry theoretical risks in pregnancy. Genticin HC should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus; a physician should be consulted before use. Use during breastfeeding should also be discussed with a physician, avoiding application to the breast area, and using the smallest effective amount for the shortest possible duration.

Take Genticin HC exactly as prescribed by your physician; do not stop, extend, skip doses, or share this medicine with others without medical advice.

• Duration of use: Use for the shortest period necessary; avoid prolonged, repeated, or intermittent long-term use, which increases the risk of bacterial resistance, ototoxicity, nephrotoxicity, and steroid-related skin damage.
• Extent of application: Do not apply Genticin HC to large areas of skin, broken/denuded skin, or under occlusive dressings unless specifically directed by a physician, as this increases systemic absorption and the risk of ototoxicity, nephrotoxicity, and HPA-axis suppression.
• Ear use: Confirm with a physician that the eardrum is intact before using the ear drop formulation of Genticin HC (see Contraindications).
• Not for ophthalmic use: Avoid contact with the eyes; Genticin HC is not intended for use in or around the eyes.
• Superinfection: Prolonged use of Genticin HC may result in overgrowth of non-susceptible organisms, including fungi; discontinue and consult a physician if new or worsening infection develops.
• Masking of infection: The corticosteroid component may mask signs of untreated infection or delay wound healing.
• If no improvement occurs within 7 days, or if the condition worsens, stop Genticin HC and consult a physician.

Overdose from normal topical or otic use of Genticin HC is unlikely, but excessive or prolonged application over large areas, or accidental ingestion, may increase the risk of systemic effects such as ototoxicity, nephrotoxicity, or corticosteroid-related effects. If accidental ingestion of Genticin HC occurs, or if signs of systemic toxicity (such as hearing changes, dizziness, or reduced urine output) develop, seek immediate medical attention or contact a poison control center; do not attempt home treatment.

Store at room temperature (below 30°C), away from light and moisture. Do not freeze. Keep the container tightly closed and out of the reach and sight of children.

Children: Use Genticin HC with caution in infants and young children, who have a higher skin-surface-to-body-weight ratio and are therefore more susceptible to systemic absorption, HPA-axis suppression, and growth effects with prolonged corticosteroid use, as well as aminoglycoside-related toxicity; use for the shortest effective duration and avoid occlusive dressings.

Elderly: Age-related skin thinning may increase local absorption of Genticin HC; use the lowest effective amount for the shortest duration.

Renal impairment: Although systemic absorption of Genticin HC is normally minimal, caution is advised in patients with renal impairment or extensive skin/ear canal breakdown, as increased systemic exposure raises the risk of nephrotoxicity and ototoxicity.

Hepatic impairment: No specific dose adjustment for Genticin HC is established; use as directed by a physician.

Treatment with Genticin HC should generally be limited to 7–10 days for skin conditions and up to 7 days for otitis externa. If symptoms do not improve within this period, or recur soon after stopping, a physician should reassess the diagnosis and treatment; prolonged or repeated courses of Genticin HC should be avoided unless specifically directed by a physician.

Gentamicin + Hydrocortisone Acetate combines an aminoglycoside antibiotic with a corticosteroid; it is classified as a topical/otic anti-infective and anti-inflammatory combination.

In Gentamicin + Hydrocortisone Acetate, the antibiotic component exerts a bactericidal effect by binding to the bacterial 30S ribosomal subunit and disrupting protein synthesis, while the corticosteroid component binds intracellular glucocorticoid receptors to switch off inflammatory gene expression, together controlling susceptible bacterial infection and its associated local inflammation.

The safety and efficacy of Genticin HC in children have not been as extensively established as in adults. When used, it should be applied to the smallest area necessary, for the shortest possible duration, and occlusive dressings should be avoided, because children are at greater risk of systemic absorption leading to HPA-axis suppression and aminoglycoside-related toxicity. Use of Genticin HC in infants and young children should only be under direct medical supervision.