Skip to main content

Neomycin, Colistin, Hydrocortisone, and Thonzonium

Medically reviewed by Last updated on Sep 11, 2020.


(nee oh MYE sin, koe LIS tin, hye droe KOR ti sone, & thon ZOE nee um)

Index Terms

  • Colistin, Hydrocortisone, Neomycin, and Thonzonium
  • Hydrocortisone, Neomycin, Colistin, and Thonzonium
  • Thonzonium, Neomycin, Colistin, and Hydrocortisone

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Suspension, otic [drops]:

Coly-Mycin S: Neomycin 0.33%, colistin 0.3%, hydrocortisone acetate 1%, and thonzonium bromide 0.05% (10 mL [DSC]) [contains thimerosal]

Cortisporin-TC: Neomycin 0.33%, colistin 0.3%, hydrocortisone acetate 1%, and thonzonium bromide 0.05% (10 mL) [contains thimerosal]

Brand Names: U.S.

  • Coly-Mycin S [DSC]
  • Cortisporin-TC

Pharmacologic Category

  • Antibiotic, Otic
  • Antibiotic/Corticosteroid, Otic
  • Corticosteroid, Otic


Colistin: Penetrates and disrupts bacterial cell membrane.

Hydrocortisone: Decreases inflammation by suppression of migration of polymorphonuclear leukocytes and reversal of increased capillary permeability.

Neomycin: Interferes with bacterial protein synthesis by binding to 30S ribosomal subunits.

Thonzonium: Promotes tissue contact by dispersion and penetration of the cellular debris and exudate.

Use: Labeled Indications

Otic infections: Treatment of superficial bacterial infections of the external auditory canal (otitis media); treatment of infections of mastoidectomy and fenestration cavities


Hypersensitivity to neomycin, colistin, hydrocortisone, thonzonium, or any component of the formulation; cutaneous viral infection (eg, herpes simplex virus, varicella zoster virus) of the external auditory canal

Documentation of allergenic cross-reactivity for aminoglycosides and corticosteroids is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Dosing: Adult

Otic infections: Otic: Instill 5 drops in affected ear(s) 3 or 4 times daily

Note: Duration of use should be limited to 10 days. Use calibrated dropper provided in packaging.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Otic infections: Children ≥1 year and Adolescents: Otic: Instill 4 drops in affected ear(s) 3 or 4 times daily

Note: Duration of use should be limited to 10 days. Use calibrated dropper provided in packaging.


For otic use only. Shake otic suspension well before using. Thoroughly cleanse external auditory canal and dry with a sterile cotton applicator. Patient should lie down with affected ear upward and medication instilled. This position should be maintained for 5 minutes to facilitate penetration of the drops. Repeat, if necessary, for the opposite ear. Alternatively, a cotton wick may be inserted into the canal and the cotton may be saturated with the suspension; keep wick moist by adding suspension every 4 hours. Replace wick at least once every 24 hours. Otic preparations should not be used when the integrity of the tympanic membrane is in question (AAP [Rosenfeld 2014]).


Store at 20°C to 25°C (68°F to 77°F).

Drug Interactions

There are no known significant interactions.

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

Frequency not defined.

Dermatologic: Skin irritation

Hypersensitivity: Local hypersensitivity reaction

Otic: Ototoxicity (rare)


Concerns related to adverse effects:

• Adrenal suppression: Systemic absorption of topical corticosteroids may cause hypercortisolism or suppression of hypothalamic-pituitary-adrenal (HPA) axis, particularly in younger children or in patients receiving high doses for prolonged periods. HPA axis suppression may lead to adrenal crisis.

• Immunosuppression: Prolonged use of corticosteroids may also increase the incidence of secondary infection, mask acute infection (including fungal infections), prolong or exacerbate viral infections, or limit response to vaccines.

• Kaposi sarcoma: Prolonged treatment with corticosteroids has been associated with the development of Kaposi sarcoma (case reports); if noted, discontinuation of therapy should be considered (Goedert 2012).

• Neomycin sensitization: Neomycin may cause cutaneous sensitization (primarily skin rash). Symptoms of neomycin sensitization include itching, low-grade reddening with swelling, dry scaling, itching, and failure to heal. Discontinue immediately if sensitization or irritation occurs.

• Ototoxicity: Neomycin may cause permanent sensorineural hearing loss due to cochlear damage. Risk of ototoxicity is increased in patients with extended use; limit therapy to 10 days. Do not use in any patient with a perforated tympanic membrane.

• Systemic effects: Topical corticosteroids may be absorbed percutaneously. Absorption of topical corticosteroids may cause manifestations of Cushing syndrome, hyperglycemia, or glycosuria. Absorption is increased by the use of occlusive dressings, application to denuded skin, or application to large surface areas.

Special populations:

• Pediatric: Children may absorb proportionally larger amounts of corticosteroids after topical application and may be more prone to systemic effects. HPA axis suppression, intracranial hypertension, and Cushing syndrome have been reported in children receiving topical corticosteroids. Prolonged use may affect growth velocity; growth should be routinely monitored in pediatric patients.

Other warnings/precautions:

• Appropriate use: For otic use only; do not use in the eyes. If infection is not improved after 1 week, preform cultures and susceptibility tests. Avoid contaminating the bottle tip with material from the ear, fingers, or other source.

Monitoring Parameters

Neomycin sensitization (eg, low-grade reddening with swelling, dry scaling, itching, failure to heal)

Pregnancy Risk Factor C Pregnancy Considerations

Animal reproduction studies have not been conducted with this combination. Refer to the individual Neomycin and Hydrocortisone monographs for additional information.

Patient Education

What is this drug used for?

• It is used to treat ear infections.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Burning

• Stinging

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Ear irritation

• Unable to pass urine

• Change in amount of urine passed

• Trouble hearing

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.