Wobbliness (ataxia) after Diphenhydramine in dogs

The FDA has received 169 reports of wobbliness (ataxia) in dogs after Diphenhydramine. That is 3.6% of all reports for this medicine, compared with 2.6% across reports for all dog medicines.

169Reports

64%Marked serious

24%Recovered

16%Died or euthanised

Same dayTypical onset

How soon it started

Same day

77 53%

1–2 days

23 16%

3–7 days

7 4.8%

1–4 weeks

14 9.7%

Over a month

24 17%

How the animals did

Recovered

35 21%

Recovered with lasting effects

5 3.0%

Still unwell when reported

73 43%

Died

10 5.9%

Euthanised

17 10%

Not known

29 17%

Problems reported at the same time

67 40%

54 32%

47 28%

34 20%

32 19%

32 19%

31 18%

29 17%

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 Diphenhydramine cause wobbliness (ataxia) in dogs?: 169 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 the same day 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).

Wobbliness (ataxia) with similar medicines

Wobbliness (ataxia) after Melarsomine (Immiticide) 599 reports · 2.6% of its reports
Wobbliness (ataxia) after Polysulfated Glycosaminoglycan 150 reports · 2.7% of its reports
Wobbliness (ataxia) after Butorphanol 125 reports · 2.8% of its reports
Wobbliness (ataxia) after Cefpodoxime 182 reports · 4.5% of its reports
Wobbliness (ataxia) after Tramadol 168 reports · 4.5% of its reports
Wobbliness (ataxia) after Florfenicol + Mometasone + Terbinafine 430 reports · 12% of its reports
Wobbliness (ataxia) after Desoxycorticosterone Pivalate 33 reports · 1.0% of its reports
Wobbliness (ataxia) after Propofol 69 reports · 2.2% of its reports
Wobbliness (ataxia) after Dirlotapide 23 reports · 0.8% of its reports
Wobbliness (ataxia) after Isoflurane 81 reports · 2.9% of its reports

All reported side effects of Diphenhydramine in dogs · Medicines most reported with wobbliness (ataxia)