Didn't work as expected after Hydroxyzine in dogs

The FDA has received 153 reports of didn't work as expected in dogs after Hydroxyzine. That is 15% of all reports for this medicine, compared with 13% across reports for all dog medicines.

153Reports

26%Marked serious

5.2%Recovered

3.3%Died or euthanised

74 daysTypical onset

How soon it started

Same day

10 12%

1–2 days

3 3.6%

3–7 days

2 2.4%

1–4 weeks

19 23%

Over a month

49 59%

How the animals did

Recovered

2 1.3%

Recovered with lasting effects

6 3.9%

Still unwell when reported

87 57%

Euthanised

5 3.3%

Not known

53 35%

Problems reported at the same time

21 14%

20 13%

18 12%

17 11%

15 9.8%

Overdose

11 7.2%

Inappropriate schedule of drug administration

11 7.2%

Didn't stop fleas

10 6.5%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Type: medicine.

Questions owners ask

Can Hydroxyzine cause didn't work as expected in dogs?: 153 reports link the two, but a report alone does not prove the medicine was the cause: other illnesses, other medicines or coincidence can be involved. Your vet can judge it for your animal.
How soon after a dose was it reported?: In half of the reports with dates, it started within 74 days of the first dose.
What should I do?: Don't give another dose until you've spoken to your vet, and keep the packaging so you can tell them the product and dose. Your vet can also report it to the FDA (or you can, through the manufacturer or FDA form 1932a).

Didn't work as expected with similar medicines

Didn't work as expected after Melarsomine (Immiticide) 646 reports · 2.8% of its reports
Didn't work as expected after Polysulfated Glycosaminoglycan 698 reports · 13% of its reports
Didn't work as expected after Diphenhydramine 585 reports · 12% of its reports
Didn't work as expected after Butorphanol 1,022 reports · 23% of its reports
Didn't work as expected after Cefpodoxime 671 reports · 17% of its reports
Didn't work as expected after Tramadol 475 reports · 13% of its reports
Didn't work as expected after Florfenicol + Mometasone + Terbinafine 969 reports · 27% of its reports
Didn't work as expected after Desoxycorticosterone Pivalate 355 reports · 11% of its reports
Didn't work as expected after Propofol 600 reports · 20% of its reports
Didn't work as expected after Dirlotapide 712 reports · 25% of its reports

All reported side effects of Hydroxyzine in dogs · Medicines most reported with didn't work as expected