I got talked into trying Trifexis back when it first came out. My older male dog tolerated it fine but my female vomited everytime I gave it to her. I then found out I didn’t want all the extras in Trifexis (flea preventative, broad spectrum dewormer) – it’s too much chemicals. I switched back to the regular Heartguard that just does heartworm and I only administer it during heartworm season (late spring to early fall where I am) and I no longer use any chemical flea and tick preventatives or wormers.
