Melatonin side effects in dogs

256 reports sent to the FDA between 2008 and 2026 involve Melatonin in dogs. The most reported problems were loss of appetite, vomiting, lethargy. 48% were marked serious.

256Reports
48%Marked serious
0.8%Only medicine involved
25%Recovered
11%Died or euthanised
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About this medicine

Type: medicine.

Most reported side effects

54 21%
50 20%
38 15%
Excessive urination
19 7.4%
Weakness
19 7.4%
Breathing problems
16 6.3%
Behaviour change
15 5.9%
Collapse
13 5.1%
Seizures
12 4.7%

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 0.8%
Didn't prevent heartworm
2 0.8%
Didn't stop worms
1 0.4%

How soon problems started

Same day
20 12%
1–2 days
14 8.7%
3–7 days
15 9.3%
1–4 weeks
33 20%
Over a month
79 49%

Time from the first dose to the first sign, where both dates were reported (161 reports).

How the animals did

Recovered
61 24%
Recovered with lasting effects
3 1.2%
Still unwell when reported
91 36%
Died
9 3.5%
Euthanised
20 7.8%
Not known
72 28%

Breeds named most often

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

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