Dog chews imported into Germany from China and distributed under two brand names in several European countries have been linked to the appearance of neurological symptoms in a number of dogs.
More than 15 cases have been reported in Denmark alone. An unspecified number of incidents also have been reported in the Netherlands, Germany, Finland, and Estonia.
Although the FDA is aware of the situation, an agency spokesperson informed eFoodAlert that the Center for Veterinary Medicine has not received any reports or consumer complaints of werewolf syndrome in the United States associated with dog chews.
Symptoms of werewolf syndrome can vary in type and severity, ranging from spontaneous, extreme excitement, panic attacks accompanied by howling and attempts to escape, to phases of aggression, hallucinations, epileptic seizures, and even death.
Recalls and consumer advisories
Several EU member countries and the United Kingdom have issued recall notices or consumer advisories for two brands of dog chews: Barkoo and Chrisco.
Although not distributed through retail stores in all EU countries, these chews are available for purchase over the internet.
According to an advisory issued by the UK’s Food Safety Agency, consumers should avoid the following products:
- Barkoo kaustange natur 29 cm (570g; Batch/Lot code 1148655 MHD 04.2027 3200PF027; Bar code 4260077047292)
- Barkoo kauknochen, geknotet natur 11cm (150g; Batch/Lot code 1148592 MHD 07.2027 3200PF027; Bar code 4260077046875 )
- Barkoo Kauknochen geknotet 24cm (150g; Batch/Lot code 1148657 MHD05.2027 3200PF027; Bar code 4260077046899)
- Barkoo Kauknochen geknotet mit Spirulina 12cm (180g; Batch/Lot code 1148654 MHD 06.2027 3200PF027; Bar code 4260077047261)
- Chrisco Tyggeruller med kylling, 10 stk (Item #12457; All Use-by dates; EAN 5764630124578)
- Chrisco Tyggeruller med kylling & kyllingelever (100g; Product no. 12324; Use by 01/12/2025; 05-01-2026; 15-03-2026; 18-03-2026; 15-04-2026; 20-04-2026; 01-06-2026; 15-07-2026; EAN 5764630123243)
- Chrisco Tyggeruller 18 stk. – hvide (Product no. 12468; Use by 05/01/2027; 26-02-2027; 15-03-2027; 18-03-2027; 24-03-2027; EAN 5764630124684)
- Chrisco Massive politistave, 2.stk. – brune (Product no. 12541; Use by 26/02/2027; 15-04-2027; EAN 5764630125414)
- Chrisco Massive politistave, 2stk. – hvide (Product no. 12542; Use by 05/01/2027; 20-04-2027; 01-06-2027; EAN 5764630125421)
- Chrisco Tyggerulle m. kylling & kyllingelever, 1stk (Product no. 12624; Use by 01/12/2025; 05-01-2026; 15-03-2026; 18-08-2026; EAN 5764630126244)
Advice for dog owners
- If you have fed any of the llsted chews to your dog, stop doing so immediately.
- If your dog is unwell and has been fed any of these dog chews, you should seek veterinary advice and provide detailed information to the vet about the foods and treats your dog has been fed.
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“An invaluable resource for busy pet owners” – Food Safety News
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