What Are the Side Effects of Trifexis?

As with all medicines, sometimes side effects may occur. In some cases, dogs vomited after receiving Trifexis® (spinosad + milbemycin oxime). If vomiting occurs within an hour of administration, redose with another full dose. During field studies, no severe or prolonged vomiting occurred. Additional adverse reactions observed in the clinical studies were itching, decreased activity, diarrhea, inflammation of the skin, redness of the skin, decreased appetite and redness of the ear. All reactions were regarded as mild.

ADVERSE REACTIONS
The most common adverse reactions based on post-approval adverse drug event reporting are vomiting, lethargy, itching, loss of appetite, diarrhea, trembling/shaking, incoordination, seizures, excessive salivation and redness of the skin.

Average Monthly Rate (%) of Dogs With Adverse Reactions in a US Field Study

Trifexis adverse reactions chart