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dextromethorphan Side Effects

Also known as: Delsym, Robitussin

Analysis of 7,480 adverse event reports submitted to the FDA from 2004 to 2025.

Total Reports

7,480

Death-Related

1,756

23.5% of reports

Hospitalizations

1,400

18.7% of reports

Top Indication

Product Used For Unknown Indication

Most Reported Adverse Reactions

DRUG INEFFECTIVE
1,313
DRUG ABUSE
713
TOXICITY TO VARIOUS AGENTS
678
OVERDOSE
594
DIZZINESS
435
ACCIDENTAL OVERDOSE
403
DIARRHOEA
394
COMPLETED SUICIDE
333
DEATH
321
COUGH
307
NAUSEA
281
NO ADVERSE EVENT
246
DYSPNOEA
232
FATIGUE
230
VOMITING
229
DRUG INTERACTION
223
HEADACHE
215
SOMNOLENCE
207
INSOMNIA
195
PNEUMONIA
190

Who Reports Side Effects

Gender Distribution

Female 4,020 (57%)
Male 2,982 (43%)
Unknown 3

Age Distribution

0-17 1,161 (21%)
18-44 1,627 (29%)
45-64 1,432 (26%)
65-74 695 (12%)
75+ 688 (12%)

Reporting Trend by Year

2004 2025

Reactions in Death Reports

Top reactions reported in 1,756 reports where death was an outcome. These are voluntarily reported and do not establish causation.

Reaction Reports
TOXICITY TO VARIOUS AGENTS 562
DRUG ABUSE 516
COMPLETED SUICIDE 332
DEATH 321
CARDIO-RESPIRATORY ARREST 138
CARDIAC ARREST 106
OVERDOSE 98
RESPIRATORY ARREST 86
DRUG INTERACTION 85
ACCIDENTAL OVERDOSE 69
DYSPNOEA 59
POISONING 59
FATIGUE 57
OFF LABEL USE 52
PNEUMONIA 52
ASTHENIA 49
DRUG TOXICITY 48
INTENTIONAL PRODUCT MISUSE 47
INTENTIONAL OVERDOSE 46
DIARRHOEA 43

Reactions in Hospitalization Reports

Top reactions in 1,400 reports where hospitalization was an outcome.

Reaction Reports
TOXICITY TO VARIOUS AGENTS 153
PNEUMONIA 148
DYSPNOEA 127
OVERDOSE 105
SEROTONIN SYNDROME 100
DRUG INTERACTION 94
OFF LABEL USE 91
DRUG ABUSE 89
FATIGUE 87
PYREXIA 87
INTENTIONAL OVERDOSE 86
COUGH 85
MALAISE 84
HYPERTENSION 83
ANXIETY 82
NAUSEA 81
DIARRHOEA 79
DRUG INEFFECTIVE 79
VOMITING 78
CONDITION AGGRAVATED 77

Nearby — Related Medications

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What the FAERS Data Reveals About dextromethorphan Side Effects

The FDA Adverse Event Reporting System (FAERS) contains 7,480 voluntary reports linked to dextromethorphan and its brand equivalents (Delsym, Robitussin), spanning 2004 through 2025. Of those, 1,756 (23.5%) listed death as an outcome and 1,400 (18.7%) involved hospitalization. The most common indication reported alongside adverse events was Product Used For Unknown Indication.

Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 57% were female and 43% male; age distribution skews toward 18-44, with 1,627 reports in that bracket. The single most reported reaction is drug ineffective with 1,313 submissions, followed by drug abuse and toxicity to various agents.

FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice — speak with a licensed clinician about any side-effect concerns.