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Mometamax Otic Suspension (Canada)

This page contains information on Mometamax Otic Suspension for veterinary use.
The information provided typically includes the following:
  • Mometamax Otic Suspension Indications
  • Warnings and cautions for Mometamax Otic Suspension
  • Direction and dosage information for Mometamax Otic Suspension

Mometamax Otic Suspension

This treatment applies to the following species:
Company: Merck Animal Health



Antibiotic, Anti-inflammatory, Antifungal

For Otic Use in Dogs Only

DIN 02344688


Each gram of MOMETAMAX otic suspension contains gentamicin sulfate, USP equivalent to 3 mg gentamicin base; mometasone furoate monohydrate, Mfr.Std. equivalent to 1 mg mg mometasone furoate; and 10 mg clotrimazole, USP in a mineral oil-based system containing a plasticized hydrocarbon gel.

Mometamax Otic Suspension Indications

MOMETAMAX otic suspension is indicated for the treatment of otitis externa in dogs caused by yeast susceptible to clotrimazole (Malassezia pachydermatis) and bacteria susceptible to gentamicin (Pseudomonas spp. [including P. aeruginosa], coagulase-positive staphylococci [including S. aureus and S. intermedius], Enterococcus faecalis, Proteus mirabilis and beta-hemolytic streptococci), and for the reduction of tissue inflammation that is commonly associated with this condition.

Dosage and Administration

The external ear canal should be thoroughly cleaned and dried before treatment. Excessive hair should be removed from the treatment area of the external ear. Verify that the eardrum is intact. Shake well before use. For dogs weighing less than 15 kg, per affected ear, instill 4 drops from the 7.5 g, 15 g or 30 g bottle (2 drops from the 215 g bottle) of MOMETAMAX otic suspension once daily into the ear canal for 7 consecutive days. For dogs weighing 15 kg or more, per affected ear, instill 8 drops from the 7.5 g, 15 g or 30 g bottle (4 drops from the 215 g bottle) once daily into ear canal for 7 consecutive days. After application, massage the base of the ear to allow the preparation to penetrate to the lower part of the ear canal. Do not exceed the recommended period of treatment or frequency of application.


If hypersensitivity to any of the components occurs, treatment should be discontinued and appropriate therapy instituted. Concomitant use of drugs known to induce ototoxicity should be avoided. Do not use in dogs with known perforation of eardrums. Do not use in cats.


The use of these components has been associated with deafness or partial hearing loss in some dogs (e.g. geriatric). On rare occasions, especially in older dogs, permanent hearing losses or deficits were reported. If hearing loss, vestibular dysfunction (head tilt, circling, rolling, rhythmic movement of the eyes) or hypersensitivity (redness and pain) or other reactions are noted during the course of treatment, discontinue use of MOMETAMAX otic suspension immediately and flush the ear canal thoroughly with a non-ototoxic solution. Prior to treatment, it is recommended to conduct a clinical evaluation for evidence of hearing deficit and/or vestibular disorder.

Corticosteroids administered to dogs, rabbits, and rodents during pregnancy have resulted in cleft palate in offspring. Other congenital anomalies including deformed forelegs, phocomelia, and anasarca have been reported in offspring of dogs that received corticosteroids during pregnancy.

Clinical and experimental data have demonstrated that corticosteroids administered orally or parenterally to animals may induce the first stage of parturition if used during the last third of pregnancy and may precipitate premature parturition followed by dystocia, fetal death, retained placenta, and metritis.

Administration of recommended doses of MOMETAMAX otic suspension beyond 7 days may result in delayed wound healing.

If overgrowth of non-susceptible bacteria or fungi occurs, treatment should be discontinued and appropriate therapy instituted.

Avoid ingestion. Adverse systemic reactions have been observed following the oral ingestion of some topical corticosteroid preparations. Patients should be closely observed for the usual signs of adrenocorticoid overdosage which include sodium retention, potassium loss, fluid retention, weight gain, polydipsia, and/or polyuria. Prolonged use or overdosage may produce adverse immunosuppressive effects and suppression of adrenal function.

Use of corticosteroids, depending on dose, duration, and specific steroid, may result in endogenous steroid production inhibition following drug withdrawal. In patients presently receiving or recently withdrawn from corticosteroid treatments, therapy with a rapidly acting corticosteroid should be considered in especially stressful situations.

Not for ophthalmic use. Avoid contact with eyes. In case of accidental contact, rinse with copious amounts of water.

The safe use of MOMETAMAX otic suspension has not been evaluated in breeding dogs or in pregnant or lactating bitches.


Keep out of the reach of children. Wash hands carefully after applying the product. In case of accidental contact with the eyes, rinse with copious amounts of water. Do not handle the product if you have known hypersensitivity against compounds in the product.

Adverse Reactions

While aminoglycosides are absorbed poorly from skin, intoxication may occur when aminoglycosides are applied topically for prolonged periods of time to large wounds, burns, or any denuded skin, particularly if there is renal insufficiency. All aminoglycosides have the potential to produce reversible and irreversible vestibular, cochlear, and renal toxicity.

Following the use of parenteral, high-dose and/or prolonged or systemic synthetic corticosteroids, such as mometasone, in dogs, ALP (SAP) and ALT (SGPT) enzyme elevations, weight loss, anorexia, polydipsia, polyuria, neutrophilia and lymphopenia have occurred. Cushing’s syndrome in dogs has been reported in association with prolonged or repeated steroid therapy.

The following have been reported occasionally in humans in connection with the use of clotrimazole: erythema, stinging, blistering, peeling, edema, pruritus, urticaria, and general irritation of the skin not present before therapy.

Post Market Experience: Although not all adverse reactions are reported, the following adverse reaction information is based on voluntary post-approval drug experience reporting by veterinarians and pet owners/caregivers. It should be noted that suspected adverse drug reactions listed here reflect reporting and not causality. They are listed in order of decreasing frequency: Deafness, hypersensitivity, seizures, polyuria-polydipsia, vestibular syndrome, behavior problems, anorexia, diabetes, facial swelling, gastro intestinal disorders (ingestion).

Information for Pet Owners: Consult your veterinarian in case of adverse reactions to this product. In most cases, the adverse reactions are transient and disappear after termination of treatment but in rare instances may be serious especially if treatment is not discontinued. The use of this drug product has been associated with deafness or partial hearing loss in some dogs (e.g. geriatric). On rare occasions, especially in older dogs, permanent hearing losses or deficits have been reported. If hearing loss, vestibular dysfunction (head tilt, circling, rolling, rhythmic movement of the eyes) or hypersensitivity (redness and pain) are observed, it is important to discontinue the use of MOMETAMAX otic suspension immediately and contact your veterinarian. Do not exceed the recommended period of treatment or frequency of application.


Gentamicin: Gentamicin sulfate is an aminoglycoside antibiotic active against a wide variety of gram-negative and gram-positive bacteria. In vitro tests have determined that gentamicin is bactericidal and acts by inhibiting normal protein synthesis in susceptible microorganisms. In clinical trials, gentamicin was shown to have a range of activity against the following organisms commonly isolated from infected canine ears: Pseudomonas spp. (including P. aeruginosa), coagulase-positive staphylococci (including S. aureus and S. intermedius), Enterococcus faecalis, Proteus mirabilis and beta-hemolytic streptococci.

Mometasone: Mometasone furoate monohydrate is a synthetic adrenocorticoid characterized by a (2’) furoate 17-ester having chlorine at the 9 and 21 positions, which have shown to possess high topical potency.

Systemic absorption of mometasone furoate ointment was found to be low; 2% (1.2-4.1%) over one week when applied topically to dogs with intact skin. In a 6-month dermal toxicity study using 0.1% mometasone ointment on healthy intact skin in dogs, systemic effects typical of corticosteroid therapy were noted.

The extent of percutaneous absorption of topical corticosteroids is determined by many factors including the integrity of the epidermal barrier. Topical corticosteroids can be absorbed from normal, intact skin. Inflammation can increase percutaneous absorption. Once absorbed through the skin, topical corticosteroids are handled through pharmacokinetic pathways similar to systemically administered corticosteroids.

Clotrimazole: Clotrimazole is a broad-spectrum antifungal agent that is used for the treatment of dermal infections caused by various species of dermatophytes and yeast. The primary action of clotrimazole is against dividing and growing organisms.

In vitro, clotrimazole exhibits fungicidal and fungistatic activity against isolates of Malassezia pachydermatis, Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, Microsporum canis, and Candida spp. Resistance to clotrimazole is very rare among the fungi that cause superficial mycoses. In an induced otitis externa study using dogs infected with Malassezia pachydermatis, 1% clotrimazole in the vehicle formulation was effective both microbiologically and clinically in terms of reduction of exudates, odor, and swelling.

In studies of the mechanism of action, the minimum fungicidal concentration of clotrimazole caused leakage of intracellular phosphorus compounds into the ambient medium with concomitant breakdown of cellular nucleic acids and accelerated potassium efflux. These events began rapidly and extensively after addition of the drug. Clotrimazole is very poorly absorbed following dermal application.

Gentamicin-Mometasone-Clotrimazole: By virtue of its three active ingredients, MOMETAMAX otic suspension has antibacterial, anti-inflammatory, and antifungal activity. In clinical field trials, MOMETAMAX otic suspension was effective in the treatment of otitis externa associated with bacteria and Malassezia pachydermatis. MOMETAMAX otic suspension reduced discomfort, redness, swelling, exudate, and odor.


Clinical and safety studies with MOMETAMAX otic suspension have shown an adequate safety margin at the recommended dose level in dogs (see CAUTIONS/ADVERSE REACTIONS).


Store at room temperature (15°-30°C). Do not use the opened product after 28 days.

How Supplied

MOMETAMAX otic suspension is available in 7.5 g, 15 g, 30 g and 215 g plastic bottles.

To report an Adverse Reaction: 1-866-683-7838

Version: 17 January 2013

Intervet Canada Corp., subsidiary of Merck & Co., Inc., 16750, route Transcanadienne, Kirkland, QC H9H 4M7

® Registered Trademark of Intervet International B.V. Used under licence.

CPN: 1208222.3

Intervet Canada Corp.

Order Desk:   514-428-7013
Toll-Free:   866-683-7838
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