What the label lists and what reports show
Caffeine side effects
Caffeine's FDA label lists its adverse reactions in its own words. FAERS holds 2,261 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is pemphigus (989 reports).
- Generic listed
Check it at the source: the caffeine FDA label on DailyMed (effective July 29, 2026, Sagent Pharmaceuticals); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are possible side effects of caffeine citrate?Your baby may or may not develop side effects from taking caffeine citrate. Each baby is different. If your baby develops one or more of the following symptoms, speak with your baby’s doctor right away: restlessness, jitteriness, or shakiness faster heart beat increased urination (increased diaper wetting) The following symptoms may be caused by serious bowel or stomach problems. Call your baby’s doctor right away if your baby develops: bloated abdomen (stomach area) vomiting bloody stools (bloody bowel movements) loss of energy, lethargy (acting sluggish) This is not a complete list of side effects reported with caffeine citrate oral solution. If you have a concern about your baby, speak with your baby’s doctor. If you want more information about caffeine citrate oral solution, speak with your baby’s doctor or pharmacist. Distributed by: Sun Pharmaceutical Industries, Inc. […]
Source: FDA drug label (Caffeine Citrate), Sun Pharmaceutical Industries, Inc., effective December 12, 2020 (SPL set cc632825-e0a4-4524-8d7d-ce926efab3d6), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsOverall, the reported number of adverse events in the double-blind period of the controlled trial was similar for the caffeine citrate and placebo groups. The following table shows adverse events that occurred in the double-blind period of the controlled trial and that were more frequent in caffeine citrate-treated patients than placebo. ADVERSE EVENTS THAT OCCURRED MORE FREQUENTLY IN CAFFEINE CITRATE-TREATED PATIENTS THAN PLACEBO DURING DOUBLE-BLIND THERAPY Adverse Event (AE) Caffeine Citrate N=46 Placebo N=39 n (%) n (%) BODY AS A WHOLE Accidental Injury 1 (2.2) 0 (0.0) Feeding Intolerance 4 (8.7) 2 (5.1) Sepsis 2 (4.3) 0 (0.0) CARDIOVASCULAR SYSTEM Hemorrhage 1 (2.2) 0 (0.0) DIGESTIVE SYSTEM Necrotizing Enterocolitis 2 (4.3) 1 (2.6) Gastritis 1 (2.2) 0 (0.0) Gastrointestinal Hemorrhage 1 (2.2) 0 (0.0) HEMIC AND LYMPHATIC SYSTEM Disseminated Intravascular Coagulation 1 (2.2) 0 (0.0) …
ADVERSE EVENTS THAT OCCURRED MORE FREQUENTLY IN CAFFEINE CITRATE-TREATED PATIENTS THAN PLACEBO DURING DOUBLE-BLIND THERAPY
| Adverse Event (AE) | Caffeine Citrate N=46 n (%) | Placebo N=39 n (%) |
|---|---|---|
| Accidental Injury | 1 (2.2) | 0 (0.0) |
| Feeding Intolerance | 4 (8.7) | 2 (5.1) |
| Sepsis | 2 (4.3) | 0 (0.0) |
| Hemorrhage | 1 (2.2) | 0 (0.0) |
| Necrotizing Enterocolitis | 2 (4.3) | 1 (2.6) |
| Gastritis | 1 (2.2) | 0 (0.0) |
| Gastrointestinal Hemorrhage | 1 (2.2) | 0 (0.0) |
| Disseminated Intravascular Coagulation | 1 (2.2) | 0 (0.0) |
| Acidosis | 1 (2.2) | 0 (0.0) |
| Healing Abnormal | 1 (2.2) | 0 (0.0) |
| Cerebral Hemorrhage | 1 (2.2) | 0 (0.0) |
| Dyspnea | 1 (2.2) | 0 (0.0) |
| Lung Edema | 1 (2.2) | 0 (0.0) |
| Dry Skin | 1 (2.2) | 0 (0.0) |
| Rash | 4 (8.7) | 3 (7.7) |
| Skin Breakdown | 1 (2.2) | 0 (0.0) |
| Retinopathy of Prematurity | 1 (2.2) | 0 (0.0) |
| Kidney Failure | 1 (2.2) | 0 (0.0) |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
Source: FDA drug label, Sagent Pharmaceuticals, effective July 29, 2026 (SPL set 5f38c395-0093-4afd-89ec-f96e5dc0934a), via openFDA; the full label on DailyMed
What do FAERS reports show?
2,261 reports list caffeine among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1,172 are coded as a death and 1,094 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 25 reactions below, 1 is named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Caffeine: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions