Heartgard Plus side effects in dogs

158 reports sent to the FDA between 2016 and 2026 involve Heartgard Plus in dogs. The most reported problems were seizures, vomiting, lethargy. 80% were marked serious.

158Reports
80%Marked serious
0.0%Only medicine involved
8.9%Recovered
1.9%Died or euthanised
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About this medicine

Type: medicine.

Most reported side effects

Seizures
10 6.3%
Vomiting
8 5.1%
Lethargy
7 4.4%
Tremors
7 4.4%
Excessive urination
7 4.4%
Wobbliness (ataxia)
6 3.8%
Loss of appetite
6 3.8%
Urinary incontinence
6 3.8%
Weakness
5 3.2%
Itching
5 3.2%
Overdose
4 2.5%
Drug dose administration interval too long
4 2.5%
Behaviour change
4 2.5%
Diarrhea
4 2.5%
Urinary tract infection
4 2.5%

Share = percentage of this medicine's reports that mention the problem. One report can list several problems.

Reports that it didn't work

Some reports are about the medicine not working (for example a dog still getting fleas or heartworm), not about a side effect.

Didn't stop fleas
2 1.3%
Didn't work as expected
2 1.3%
Didn't stop worms
1 0.6%

How soon problems started

Same day
15 20%
1–2 days
7 9.2%
3–7 days
6 7.9%
1–4 weeks
11 14%
Over a month
37 49%

Time from the first dose to the first sign, where both dates were reported (76 reports).

How the animals did

Recovered
14 8.9%
Still unwell when reported
122 77%
Died
1 0.6%
Euthanised
2 1.3%
Not known
19 12%

Breeds named most often

Popular breeds appear more often because there are more of them.

Other medicines for dogs