The US Food and Drug Administration (FDA) on Thursday alerted pet owners and veterinarians that dogs and cats treated with tick and flea products could suffer “neurologic adverse events” such as muscle tremors and seizures.

The isoxazoline-containing products - Bravecto‚ Nexgard‚ Simparica and Credelio - are all FDA-approved for the treatment and prevention of flea and tick infestations.

Only Bravecto and Nexgard are available in SA‚ the former since 2014. Many SA pet owners have reported their pets getting ill after using the products.

Since the products being approved‚ the FDA says‚ there have been reports of “some” animals suffering “adverse events” after ingesting them.

“The FDA is working with manufacturers of (these) products to include new label information to highlight neurologic events because these events were seen consistently across the isoxazoline class of products‚” the agency said.

“Veterinarians should use their specialised training to review their patients’ medical histories and determine‚ in consultation with pet owners‚ whether a product in the isoxazoline class is appropriate for the pet.

“The FDA continues to monitor adverse drug event reports for these products and encourages pet owners and veterinarians to report adverse drug events.

“You can do this by reporting to the drugs’ manufacturers‚ who are required to report this information to the FDA‚ or by submitting a report directly to the FDA‚” it continued.

Dozens of South Africans are among the many dog owners who have reported that their dogs became ill or died after being given Bravecto‚ a product which claims to provide 12 weeks of protection against fleas and ticks with a single treatment.

Cheryl Wigmore‚ of Balgowan‚ KwaZulu-Natal - who blames Bravecto for the death of two of her dogs‚ and has a long list of other South Africans who are adamant that their dogs’ deaths or severe illnesses were caused by Bravecto - welcomed the FDA alert.

Bravecto manufacturer MSD Animal Health had paid for the autopsy of one of her dogs‚ she said‚ but not the vet bills‚ which totalled about R50‚000.

The FDA alert is currently big news on the US-based Facebook group “Does Bravecto Kill Dogs?”

Patti Winter commented: “No more denials about neurological involvement.”

In late 2016‚ when there was a wave of social media comments about the alleged adverse effects of Bravecto in SA‚ MSD Animal Health’s Dr Carolyn Chelchinskey said there was no certainty that Bravecto caused any adverse event.

“Adverse events may be related to underlying disease‚ other medications used at the same time‚ inappropriate use‚ and many other factors‚” she said.

Chelchinskey is currently on leave and a MSD Animal Health employee told TimesLIVE that only the company’s general manager in SA could comment on the FDA alert‚ and that would only be next week.

The package insert for Bravecto in SA was updated last year to warn that the product should not be given to dogs who suffer from epilepsy. It also states that the product had caused convulsions and lethargy in less than 0‚001% of cases.

TimesLIVE contacted the makers of Nexgard‚ Boehringer Ingelheim‚ on Friday morning‚ asking whether any SA consumers had reported their pets suffering adverse effects from the product‚ and what warnings appear on its package insert.

The local company is waiting for a response from its legal department at its headquarters in Germany.

This story will be updated when the comment is received.