Gentacon D

Gentacon D Uses, Dosage, Side Effects, Food Interaction and all others data.

Dexamethasone is a synthetic glucocorticoid which decreases inflammation by inhibiting the migration of leukocytes and reversal of increased capillary permeability. It suppresses normal immune response.

Corticosteroids bind to the glucocorticoid receptor, inhibiting pro-inflammatory signals, and promoting anti-inflammatory signals. Dexamethasone's duration of action varies depending on the route. Corticosteroids have a wide therapeutic window as patients may require doses that are multiples of what the body naturally produces. Patients taking corticosteroids should be counselled regarding the risk of hypothalamic-pituitary-adrenal axis suppression and increased susceptibility to infections.

Gentamicin sulphate actively transported across the bacterial cell membrane, binds to a specific receptor protein on the 30S subunit of bacterial ribosomes and interferes with an initiation complex between mRNA (messenger RNA) and the 30 S subunit, inhibiting protein synthesis. DNA may be misread, thus producing nonfunctional proteins; polyribosomes are split apart and are unable to synthesize protein.

Eye drops may be absorbed following topical application to the eye. Ear drops may be absorbed following topical application to the ear, especially if the eardrum is perforated or if tissue damage is present.

Gentamicin sulphate is active against many strains of the following microorganisms: Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus pneumoniae, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Niesseria gonorrhoea, Pseudomonus aeruginosa, and Serratia marcescens.

Trade Name Gentacon D
Generic Dexamethasone + Gentamicin
Type Ee Drops
Therapeutic Class
Manufacturer Concept Pharmaceuticals Ltd
Available Country India
Last Updated: September 19, 2023 at 7:00 am
Gentacon D
Gentacon D

Uses

Endocrine disorders: Primary or secondary adrenocortical insufficiency (hydrocortisone or cortisone is the drug of choice; synthetic analogs may be used in conjunction with mineralocorticoids where applicable; in infancy, mineralocorticoid supplementation is of particular importance). Acute adrenocortical insufficiency, pre operatively and in the event of serious trauma or illness, in patients with known adrenal insufficiency or when adrenocortical reserve is doubtful. Shock unresponsive to conventional therapy if adrenocortical insufficiency exists or is suspected congenital adrenal hyperplasia, nonsuppurative thyroiditis, hypercalcemia associated with cancer

Rheumatic disorders: As adjunctive therapy for short-term administration (to tide the patient over an acute episode or exacerbation) in: post-traumatic osteoarthritis, synovitis of osteoarthritis, rheumatoid arthritis including juvenile rheumatoid arthritis (selected cases may require low-dose maintenance therapy), acute and sub-acute bursitis, epicondylitis, acute nonspecific tenosynovitis, acute gouty arthritis, psoriatic arthritis, ankylosing spondylitis.

Collagen diseases: During an exacerbation or as maintenance therapy in selected cases of Systemic lupus erythematosus and acute rheumatic carditis

Dermatologic diseases: Pemphigus,Severe erythema multiforme (Stevens-Johnson syndrome), Exfoliative dermatitis, Bullous dermatitis herpetiformis, Severe seborrheic dermatitis,Severe psoriasis, Mycosis fungoides

Allergic states: Control of severe or incapacitating allergic conditions intractable to adequate trials of conventional treatment in bronchial asthma, contact dermatitis, atopic dermatitis, serum sickness, seasonal or perennial allergic rhinitis, drug hypersensitivity reactions, urticarial transfusion reactions, acute non-infectious laryngeal edema (epinephrine is the drug of first choice)

Ophthalmic diseases: Severe acute and chronic allergic and inflammatory processes involving the eye, such as: herpes zoster ophthalmicus, iritis, iridocyclitis, chorioretinitis, diffuse posterior uveitis and choroiditis, optic neuritis, sympathetic ophthalmia, anterior segment inflammation, allergic conjunctivitis, keratitis, allergic corneal marginal ulcers.

Gastrointestinal diseases: To tide the patient over a critical period of the disease in ulcerative colitis (systemic therapy), regional enteritis (systemic therapy) Respiratory diseases Symptomatic sarcoidosis, berylliosis, fulminating or disseminated pulmonary tuberculosis when used concurrently with appropriate anti-tuberculous chemotherapy, Loeffler's syndrome not manageable by other means, aspiration pneumonitis.

Hematologic disorders: Acquired (autoimmune) hemolytic anemia, idiopathic thrombocytopenic purpura in adults (I.V. only: I.M administration is contraused), secondary thrombocytopenia in adults, erythroblastopenia (RBC anemia), congenital (erythroid) hypoplasticanemia

Neoplastic diseases: For palliative management of leukemias and lymphomas in adults, acute leukemia of childhood.

Edematous states: To induce diuresis or remission of proteinuria in the nephrotic syndrome, without uremia, of the idiopathic type or that due to lupus erythematosus.

Miscellaneous: Tuberculous meningitis with subarachnoid block or impending block when used concurrently with appropriate antituberculous chemotherapy,Trichinosis with neurologic or myocardial involvement

Cerebral Edema: Cerebral Edema associated with primary or metastatic brain tumor, craniotomy, or head injury. Use in cerebral edema is not a substitute for careful neurosurgical evaluation and definitive management such as neurosurgery or other specific therapy.May also be useful in cystic tumors of an aponeurosis or tendon (ganglia).

Blepharitis, blepharoconjunctivitis, conjunctivitis, dacryocystitis, keratitis, keratoconjunctivitis, acute meibomianitis, and corneal ulcers caused by susceptible organisms. Otorrhea associated with external otitis, chronic suppurative otitis media or subacute purulent otitis media; or postoperative otorrhea, such as that following fenestration, mastoidectomy or tympanoplasty.

Gentamicin cream is used for the topical treatment of the primary and secondary bacterial infections of the skin caused by the organisms sensitive to Gentamicin. Gentamicin may clear infections that have not responded to other topical antibiotics.

Gentacon D is also used to associated treatment for these conditions: Acne Rosacea, Acute Gouty Arthritis, Acute Otitis Externa, Acute Otitis Media, Adrenal cortical hypofunctions, Adrenocortical Hyperfunction, Alopecia Areata (AA), Ankylosing Spondylitis (AS), Anterior Segment Inflammation, Aspiration Pneumonitis, Asthma, Atopic Dermatitis (AD), Berylliosis, Bullous dermatitis herpetiformis, Bursitis, Chorioretinitis, Choroiditis, Congenital Adrenal Hyperplasia (CAH), Congenital Hypoplastic Anemia, Conjunctivitis, Conjunctivitis allergic, Corneal Inflammation, Cushing's Syndrome, Dermatitis, Dermatitis exfoliative generalised, Dermatitis, Contact, Diabetic Macular Edema (DME), Discoid Lupus Erythematosus (DLE), Drug hypersensitivity reaction, Edema of the cerebrum, Epicondylitis, Episcleritis, Erythroblastopenia, Eye Infections, Eye allergy, Eye swelling, Glaucoma, Hypercalcemia, Idiopathic Thrombocytopenic Purpura, Infection, Inflammation, Inflammation of the External Auditory Canal, Intraocular Inflammation, Iridocyclitis, Iritis, Keloid Scars, Leukemia, Acute, Lichen Planus (LP), Lichen simplex chronicus, Loeffler's syndrome, Macular Edema, Malignant Lymphomas, Middle ear inflammation, Mucosal Inflammation of the eye, Multiple Myeloma (MM), Muscle Inflammation caused by Cataract Surgery of the eye, Mycosis Fungoides (MF), Necrobiosis lipoidica diabeticorum, Noninfectious Posterior Uveitis, Ocular Infections, Irritations and Inflammations, Ocular Inflammation, Ocular Inflammation and Pain, Ocular Irritation, Ophthalmia, Sympathetic, Optic Neuritis, Otitis Externa, Pemphigus, Perennial Allergic Rhinitis (PAR), Phlyctenular keratoconjunctivitis, Post-traumatic Osteoarthritis, Postoperative Infections of the eyes caused by susceptible bacteria, Regional Enteritis, Rheumatoid Arthritis, Rheumatoid Arthritis, Juvenile, Sarcoidosis, Scleritis, Seasonal Allergic Conjunctivitis, Seasonal Allergic Rhinitis, Secondary thrombocytopenia, Serum Sickness, Severe Seborrheic Dermatitis, Stevens-Johnson Syndrome, Synovitis, Systemic Lupus Erythematosus (SLE), Trichinosis, Tuberculosis (TB), Tuberculosis Meningitis, Ulcerative Colitis, Uveitis, Vernal Keratoconjunctivitis, Acquired immune hemolytic anemia, Acute nonspecific tenosynovitis, Acute rheumatic carditis, Corticosteroid-responsive dermatoses, Ear infection-not otherwise specified caused by susceptible bacteria, Granuloma annulare lesions, Non-suppurative Thyroiditis, Ocular bacterial infections, Severe Psoriasis, Steroid-responsive inflammation of the eye, Varicella-zoster virus acute retinal necrosis, Watery itchy eyesBacterial Conjunctivitis, Bacterial Infections, Bacterial Peritonitis, Bacterial dacryocystitis, Blepharoconjunctivitis, Central Nervous System Infections, Conjunctivitis allergic, Corneal infection, Dermatitis infected, Ecthyma, Eczematous dermatitis infected, Folliculitis, Furunculosis, Gram-negative enteric bacilli neonatal sepsis, Impetigo contagious, Inflammation, Keratitis bacterial, Keratoconjunctivitis, Meibomianitis, Meningitis, Bacterial, Ocular Inflammation, Pustular Psoriasis (PP), Pustular acne, Pyoderma Gangrenosum, Seborrheic Dermatitis, Septicemia gram-negative, Skin Infections, Skin Infections, Bacterial, Skin and Subcutaneous Tissue Bacterial Infections, Sycosis barbae, Bacterial blepharitis, Bacterial corneal ulcers, Bacterial dermatoses, Complicated Bacterial Urinary Tract Infections, Complicated Respiratory tract infection bacterial, Corticosteroid-responsive dermatoses, Ocular bacterial infections, Severe Endocarditis enterococcal, Severe Infection Pseudomonas aeruginosa, Severe Staphylococcal infection

How Gentacon D works

The short term effects of corticosteroids are decreased vasodilation and permeability of capillaries, as well as decreased leukocyte migration to sites of inflammation. Corticosteroids binding to the glucocorticoid receptor mediates changes in gene expression that lead to multiple downstream effects over hours to days.

Glucocorticoids inhibit neutrophil apoptosis and demargination; they inhibit phospholipase A2, which decreases the formation of arachidonic acid derivatives; they inhibit NF-Kappa B and other inflammatory transcription factors; they promote anti-inflammatory genes like interleukin-10.

Lower doses of corticosteroids provide an anti-inflammatory effect, while higher doses are immunosuppressive. High doses of glucocorticoids for an extended period bind to the mineralocorticoid receptor, raising sodium levels and decreasing potassium levels.

There are 3 key phases of aminoglycoside entry into cells. The first “ionic binding phase” occurs when polycationic aminoglycosides bind electrostatically to negatively charged components of bacterial cell membranes including with lipopolysaccharides and phospholipids within the outer membrane of Gram-negative bacteria and to teichoic acids and phospholipids within the cell membrane of Gram-positive bacteria. This binding results in displacement of divalent cations and increased membrane permeability, allowing for aminoglycoside entry. The second “energy-dependent phase I” of aminoglycoside entry into the cytoplasm relies on the proton-motive force and allows a limited amount of aminoglycoside access to its primary intracellular target - the bacterial 30S ribosome. This ultimately results in the mistranslation of proteins and disruption of the cytoplasmic membrane.[A233320] Finally, in the “energy-dependent phase II” stage, concentration-dependent bacterial killing is observed. Aminoglycoside rapidly accumulates in the cell due to the damaged cytoplasmic membrane, and protein mistranslation and synthesis inhibition is amplified. The necessity of oxygen-dependent active transport explains why aminoglycosides are ineffective against anaerobic bacteria. Hence, aminoglycosides have both immediate bactericidal effects through membrane disruption and delayed bactericidal effects through impaired protein synthesis; observed experimental data and mathematical modeling support this two-mechanism model. Inhibition of protein synthesis is a key component of aminoglycoside efficacy. Structural and cell biological studies suggest that aminoglycosides bind to the 16S rRNA in helix 44 (h44), near the A site of the 30S ribosomal subunit, altering interactions between h44 and h45. This binding also displaces two important residues, A1492 and A1493, from h44, mimicking normal conformational changes that occur with successful codon-anticodon pairing in the A site.[A232324, A232329] Overall, aminoglycoside binding has several negative effects including inhibition of translation, initiation, elongation, and ribosome recycling. Recent evidence suggests that the latter effect is due to a cryptic second binding site situated in h69 of the 23S rRNA of the 50S ribosomal subunit.[A232329, A232339] Also, by stabilizing a conformation that mimics correct codon-anticodon pairing, aminoglycosides promote error-prone translation.[A232344] Mistranslated proteins can incorporate into the cell membrane, inducing the damage discussed above.

Dosage

Gentacon D dosage

Intraarticular-

Inflammatory joint diseases:

  • Adult: 0.8-4 mg depending on the size of the affected joint. For soft-tissue inj, 2-6 mg may be used. May repeat inj every 3-5 days to every 2-3 wk.

Intravenous-

Prophylaxis of nausea and vomiting associated with cytotoxic therapy:

  • Adult: Prevention: 10-20 mg 15-30 minutes before admin of chemotherapy on each treatment day. For continuous infusion regimen: 10 mg every 12 hr on each treatment day. For midly emetogenic regimen: 4 mg every 4-6 hr.

Unresponsive shock:

  • Adult: As phosphate: Initially, 40 mg or 1-6 mg/kg as a single IV inj, may repeat every 2-6 hr. Continue high-dose treatment only until patient's condition has stabilised and not to be continued beyond 48-72 hr.

Bacterial meningitis:

  • Adult: 0.15 mg/kg 4 times daily, to be given 10-20 min before or with the 1st dose of anti-infective treatment. Treatment should be given for the first 2-4 days of the anti-infective treatment.
  • Child: As phosphate: 2 mth-18 yr: 150 mcg/kg every 6 hr for 4 days, starting before or with 1st dose of antibacterial treatment.

Cerebral oedema caused by malignancy:

  • Adult: As phosphate: 10 mg IV followed by 4 mg IM every 6 hr until response is achieved, usually after 12-24 hr. May reduce dosage after 2-4 days then gradually discontinued over 5-7 days. In severe cases, an initial dose of 50 mg IV may be given on day 1, with 8 mg every 2 hr, reduced gradually over 7-13 days. Maintenance dose: 2 mg 2-3 times daily.
  • Child: As phosphate: 35 kg: Initially 25 mg, then 4 mg every 2 hr for 3 days, then 4 mg every 4 hr for 1 day, then 4 mg every 6 hr for 4 days, then decrease by 2 mg daily. Doses are given via IV inj.

Oral-

Anti-inflammatory:

  • Adult: 0.75-9 mg daily in 2-4 divided doses; may also be given via IM/IV admin.
  • Child: 1 mth-18 yr: 10-100 mcg/kg daily in 1-2 divided doses via oral admin, adjusted according to response; up to 300 micrograms/kg daily may be used in emergency situations.

Screening test for Cushing's syndrome:

  • Adult: 0.5 mg every 6 hr for 48 hr after determining baseline 24-hr urinary 17-hydroxycorticosteroid (17-OHCS) concentrations. During the second 24 hr of dexamethasone admin, urine is collected and analysed for 17-OHCS. Alternatively, after a baseline plasma cortisol determination, 1 mg may be given at 11 pm and plasma cortisol determined at 8 am the next morning. Plasma cortisol and urinary output of 17-OHCS are depressed after dexamethasone admin in normal individuals but remain at basal levels in patients with Cushing's syndrome.

Acute exacerbations in multiple sclerosis:

  • Adult: 30 mg daily for 1 wk followed by 4-12 mg daily for 1 mth.
  • Child: 1 mth-12 yr: 100-400 mcg/kg daily in 1-2 divided doses; 12-18 yr: Initially 0.5-24 mg daily. Max. 24 mg daily.

Eye: 1-2 drops instilled in affected eye up to 6 times a day or more frequently if required (severe infections may require 1-2 drops every 15-20 minutes initially, reducing the frequency of instillation gradually as the infection is controlled).

Ear: The area should be cleaned and 2-3 drops should be instilled every 3-4 times a day and at night, or more frequently if required.

A small amount of Gentamicin should be applied gently to the affected areas three to four times daily. The area treated may be covered with a gauze dressing if desired. Before applying the medication the affected area should be properly cleaned.

Side Effects

Dexamethasone is generally well tolerated in standard low doses, Nausea, vomiting, increased appetite, and obesity may occur. Higher doses may result behavioral personality changes. Following adverse reactions have been associate with prolonged systemic glucocorticoid therapy, endocrine & metabolic disturbances, fluid & electrolyte disturbances, musculo-skeletal effects like osteoporosis etc; GI effects like ulcer, bleeding, perforation; Opthelmic effects like Glaucoma, increased intraocular pressure etc; immunosuppressive effects like increased susceptibility to infection etc.

In patients with dermatoses treated with gentamicin, irritation (erythema and pruritus) had been reported in small number of cases. Itching, redness, swelling or other signs of irritation may develop. With the eye/ear drop bacterial and corneal ulcer have developed during treatment with gentamicin. Most frequently reported adverse reactions are ocular burning and irritation upon drug instillation, non specific conjunctivitis, conjunctival epithelial defects, and conjunctival hyperemia.

Gentamicin cream is well tolerated. There has been no evidence of irritation and sensitization after using Gentamicin cream.

Toxicity

The oral LD50 in female mice was 6.5g/kg and 794mg/kg via the intravenous route.

Overdoses are not expected with otic formulations. Chronic high doses of glucocorticoids can lead to the development of cataract, glaucoma, hypertension, water retention, hyperlipidemia, peptic ulcer, pancreatitis, myopathy, osteoporosis, mood changes, psychosis, dermal atrophy, allergy, acne, hypertrichosis, immune suppression, decreased resistance to infection, moon face, hyperglycemia, hypocalcemia, hypophosphatemia, metabolic acidosis, growth suppression, and secondary adrenal insufficiency. Overdose may be treated by adjusting the dose or stopping the corticosteroid as well as initiating symptomatic and supportive treatment.

As with other aminoglycosides, nephrotoxicity and ototoxicity are associated with gentamicin. Signs of nephrotoxicity include an increase in plasma creatinine and urea, while signs of ototoxicity include issues with balance, nausea, tinnitus, and hearing loss. It is important to note that aminoglycoside-induced nephrotoxicity is typically reversible, while ototoxicity is more likely to be permanent. The risk of both toxicities increases with long-term gentamicin therapy. Gentamicin is considered to be more vestibulotoxic than cochleotoxic compared to other aminoglycosides. Unfortunately, gentamicin-related ototoxicity does not correlate with cumulative dosing, peak and trough levels, or dosing schedule. The unpredictability of ototoxicity supports close monitoring of the patient throughout treatment. In cases of toxicity or overdose, the medication should be discontinued immediately; hemodialysis may be initiated to lower gentamicin serum concentrations.

Precaution

The lowest possible dose of corticosteroids should be used to control the conditions under treatment. Dexamethasone should be used with caution in patient with cardiomyopathy, heart failure, hypertension, or renal insufficiency, drug induced secondary adrenocortical insufficiency, peptic ulcer, diverticulitis, intestinal anastomosis, ulcerative colitis, osteoporosis, & latent tuberculosis etc.

If these occurs or if irritation, sensitization develops, treatment with gentamicin should be discontinued and appropriate therapy instituted. Gentamicin ear/eye drops is not for injection. It should never be injected subconjunctivally, nor it should be directly introduced into the anterior chamber of the eye.

Use of topical antibiotics occasionally cause overgrowth of nonsusceptible organisms including fungi. If this occurs or if irritation, sensitisation or super infection develops, treatment with Gentamicin should be discontinued and appropriate therapy should be instituted.

Interaction

Drug interaction can be occurred with following drugs:Diuretics, cardiac glycosides, antidiabetics, NSAIDs, anticoagulants, antacids etc. Besides, if patients undergo long-term therapy of glucororticoids with concomitant salicylates, any reduction in glucocorticoid dosage should be made with caution, since salicylate intoxication has been reported in such cases.

None has been reported so far with topical and Eye/Ear drops.

Volume of Distribution

A 1.5mg oral dose of dexamethasone has a volume of distribution of 51.0L, while a 3mg intramuscular dose has a volume of distribution of 96.0L.

Elimination Route

Absorption via the intramuscular route is slower than via the intravenous route. A 3mg intramuscular dose reaches a Cmax of 34.6±6.0ng/mL with a Tmax of 2.0±1.2h and an AUC of 113±38ng*h/mL. A 1.5mg oral dose reaches a Cmax of 13.9±6.8ng/mL with a Tmax of 2.0±0.5h and an AUC of 331±50ng*h/mL. Oral dexamethasone is approximately 70-78% bioavailable in healthy subjects.

Half Life

The mean terminal half life of a 20mg oral tablet is 4 hours. A 1.5mg oral dose of dexamethasone has a half life of 6.6±4.3h, while a 3mg intramuscular dose has a half life of 4.2±1.2h.

One study assessing the pharmacokinetics of gentamicin in children and adults reported a mean half-life of 75 minutes after intravenous administration. The mean half-life associated with intramuscular administration was about 29 minutes longer. Fever and anemia may result in a shorter half-life although dose adjustments are not usually necessary. Severe burns are also associated with a shorter half-life and may result in lower gentamicin serum concentrations.

Clearance

A 20mg oral tablet has a clearance of 15.7L/h. A 1.5mg oral dose of dexamethasone has a clearance of 15.6±4.9L/h while a 3.0mg intramuscular dose has a clearance of 9.9±1.4L/h.

The renal clearance of gentamicin is comparable to individual creatinine clearance.

Elimination Route

Corticosteroids are generally eliminated predominantly in the urine. However, dexamethasone is 15

Gentamicin is excreted primarily by the kidneys. In patients with normal renal function, 70% or more of an initial gentamicin dose can be recovered in the urine within 24 hours. Excretion of gentamicin is significantly reduced in patients with renal impairment.

Pregnancy & Breastfeeding use

Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Corticosteroids should be used during pregnancy only if the potential benefit justifies. Glucocorticoids appear in breast milk, Mothers taking high dosages of corticosteroids should be advised not to breast-feed.

Consideration should be given the possibility of foetal ototoxicity when gentamicin is applied topically to large denuded areas of skin. For Gentamicin Eye/Ear Drops safety profile in pregnancy is not yet established and should be administered when considered essential.

Contraindication

In case of adrenal insufficiency, no absolute contraindications are applicable. In the treatment of non endocrine diseases where pharmacological doses are more likely to be used, the contraindications have to be considered carefully.

Relative contraindications include the followings: patient with Cushing’s syndrome, Osteoporosis, Diabetes mellitus, renal insufficiency, gastrointestinal ulcers, systemic fungal infection & acute infection.

Gentamicin is contraindicated in individuals with a history of sensitivity reaction to any of its components. Use of topical Gentamicin may occasionally allow overgrowth of nonsusceptible organisms, including fungi.

Acute Overdose

Overdose is unlikely; however, treatment of overdose is by supportive and symptomatic therapy.

Storage Condition

Store at 15-30° C.

To avoid contamination, do not touch the tip of the container to the eye, eyelid or any surface.

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