Atopica Side Effects

Please note - some side effects for Atopica may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Atopica Side Effects - for the Professional


A total of 265 dogs were included in the field study safety analysis. One hundred and

eleven (111) dogs were treated with placebo for the first 30 days. For the remainder of

the study, all dogs received Atopica capsules.

Fourteen dogs withdrew from the study due to adverse reactions. Four dogs withdrew

from the study after vomiting. One dog each withdrew from the study after diarrhea;

vomiting, diarrhea and pruritus; vomiting, depression and lethargy; lethargy, anorexia

and hepatitis; gingival hyperplasia, lethargy, polyuria/polydipsia and soft stool; seizure;

sebaceous cyst; pruritus; erythema; or otitis externa.

Vomiting and diarrhea were the most common adverse reactions occurring during the

study. In most cases, signs spontaneously resolved with continued dosing. In other

cases, temporary dose modifications (brief interruption in dosing, divided dosing, or

administration with a small amount of food) were employed to resolve signs.

Persistent otitis externa, urinary tract infections, anorexia, gingival hyperplasia,

lymphadenopathy and lethargy were the next most frequent adverse events observed.

Gingival hyperplasia regressed with dose tapering. Owners of four dogs reported

seizures while dogs were receiving Atopica. In one dog, seizures were the result of a

brain tumor diagnosed one month into the study. Another dog experienced seizures

before and after the study.

Otitis externa, allergic otitis, or pinna erythema, with or without exudates, commonly

accompanies atopy. Many dogs entered the study with otitis externa, which did not

resolve without otic treatment. New cases of otitis externa, allergic otitis, or pinna

erythema developed while dogs were receiving Atopica. However, the incidence rate

was lower with Atopica compared to placebo. A change in the dose frequency was

not necessary when new cases occurred.

Number of Dogs Displaying Each Clinical Observation in the Field Study

The following clinical signs were reported in less than 2% of dogs treated with Atopica

in the field study: constipation, flatulence, Clostridial organisms in the feces, nausea,

regurgitation, polyuria/polydipsia, strong urine odor, proteinuria, pruritus, erythema/flushed

appearance, pyoderma, sebaceous adenitis, crusty dermatitis, excessive shedding,

coarse coat, alopecia, papillomas, histiocytoma, granulomatous mass or lesion,

cutaneous cyst, epulis, benign epithelial tumor, multiple hemangioma, raised nodule on

pinna, seizure, shaking/trembling, hind limb twitch, panting, depression, irritability,

hyperactivity, quieter, increased light sensitivity, reluctance to go outside, weight loss,


The following clinical signs were observed in 1.5-4.5% of dogs while receiving the

placebo: vomiting, diarrhea and urinary tract infection. The following clinical signs were

observed in less than 1% of dogs receiving the placebo: anorexia, otitis externa, cutaneous

cysts, corneal opacity, lymphadenopathy, erythema/flushed appearance.

Clinical Pathology Changes: During the study, some dogs experienced changes in

clinical chemistry parameters while receiving Atopica, as described in the following



In addition, the following changes in clinical chemistry parameters were noted in less

than 2% of dogs: hypernatremia; hyperkalemia, elevated ALT, elevated ALP, hypercalcemia

and hyperchloremia. These clinical pathology changes were generally not associated

with clinical signs.

Post-approval Experience:

Neoplasms have been reported in dogs taking Atopica, including reports of lymphosarcoma

and mast cell tumor. It is unknown if these were preexisting or developed de novo 

while on Atopica.

In post-approval drug experience reporting, the following additional adverse reactions have

been associated with Atopica administration in dogs: vomiting, diarrhea, depression/

lethargy, anorexia, pruritus, liver enzyme elevations, trembling, convulsions, polydipsia,

polyuria, weight loss, hyperactivity, nervousness, neoplasia.

To report suspected adverse reactions or for technical assistance, call 1-800-332-2761.


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