Morphine side effects in cats

58 reports sent to the FDA between 2012 and 2025 involve Morphine in cats. The most reported problems were loss of appetite, lethargy, vomiting. 55% were marked serious.

58Reports
55%Marked serious
0.0%Only medicine involved
29%Recovered
19%Died or euthanised
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About this medicine

Type: medicine.

Most reported side effects

Loss of appetite
16 28%
Lethargy
13 22%
Vomiting
11 19%
Restlessness or agitation
10 17%
Behaviour change
9 16%
Kidney problems
7 12%
Swelling
6 10%
Weight loss
6 10%
Breathing problems
6 10%
Hyponatremia
6 10%
Fever
5 8.6%
Hypokalaemia
5 8.6%
Liver problems
4 6.9%
Hypothermia
4 6.9%
Dilated pupils
4 6.9%

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 cat still getting fleas or heartworm), not about a side effect.

Didn't work as expected
7 12%
Didn't stop fleas
1 1.7%

How soon problems started

Same day
29 55%
1–2 days
16 30%
3–7 days
4 7.5%
1–4 weeks
0 0.0%
Over a month
4 7.5%

Time from the first dose to the first sign, where both dates were reported (53 reports).

How the animals did

Recovered
17 29%
Still unwell when reported
13 22%
Died
5 8.6%
Euthanised
6 10%
Not known
17 29%

Breeds named most often

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

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