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Midol Traditional Side Effects

Generic name: aspirin / caffeine

Medically reviewed by Last updated on Feb 11, 2024.

Note: This document contains side effect information about aspirin / caffeine. Some dosage forms listed on this page may not apply to the brand name Midol Traditional.

Applies to aspirin / caffeine: oral packet, oral tablet.

Serious side effects of Midol Traditional

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Other side effects of Midol Traditional

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

For Healthcare Professionals

Applies to aspirin / caffeine: oral powder for reconstitution, oral tablet, oral tablet effervescent.


The more commonly reported adverse events with aspirin have included gastrointestinal events such as nausea and dyspepsia; caffeine may cause nervousness, irritability, sleeplessness, and palpitations, especially with higher doses.[Ref]


Endoscopically identifiable gastric mucosal lesions occur in most patients who receive a single dose of aspirin. Clinically evident gastrointestinal bleeding has been reported in as many as 3% of treated elderly patients. Anorectal ulceration and rectal stenosis have been reported in patients who abuse aspirin-containing rectal suppositories.[Ref]


Very Common (10% or more): Epigastric distress (up to 83%)

Common (1% to 10%): Abdominal discomfort/pain, endoscopically identifiable gastric mucosal lesions, nausea, vomiting

Frequency not reported: Hemorrhage, peptic ulcers, perforation, esophageal ulcerations, dyspepsia, gastritis[Ref]



Frequency not reported: Predictable antiplatelet effects, hemorrhage, increased blood fibrinolytic activity, hypoprothrombinemia, thrombocytopenia, thrombocyturia, megaloblastic anemia, pancytopenia, aplastic anemia, ecchymosis



Very common (10% or more): Hypersensitivity reactions in asthmatics who are aspirin-sensitive (e.g., with the clinical triad of aspirin sensitivity, bronchial asthma, and nasal polyps)

Frequency not reported: Hypersensitivity reactions include bronchospasm, rhinitis, conjunctivitis, urticaria, angioedema, sin reactions, and anaphylaxis



Frequency not reported: Bronchospasm (in patients sensitive to aspirin and other NSAID)



Frequency not reported: Renal dysfunction, renal failure, increased blood uric acid levels

The mechanism of an aspirin-induced decrease in renal function may be related to inhibition of renal prostaglandin synthesis with consequent decreases in renal blood flow. Vasodilating renal prostaglandins may be particularly important in patients who exhibit arterial underfilling (i.e. heart failure, cirrhosis). The administration of high doses of NSAIDs to such patients has produced acute renal failure in rare instances.



Frequency not reported: Reye's syndrome, tinnitus, temporary hearing loss


Frequency not reported: Fibrocystic breast disease

In one study of the effects of caffeine, 634 women with fibrocystic breast disease (compared to 1066 women without the disease), the occurrence of fibrocystic breast disease was positively associated with average daily consumption of caffeine. Women who consumed 31 to 250 mg/day of caffeine were reported to have a 1.5 times increase in odds to have the disease. Women who consumed over 500 mg/day of caffeine were reported to have a 2.3 times increase in odds



Frequency not reported: Stevens-Johnson syndrome, lichenoid eruption



Frequency not reported: Hepatotoxicity, cholestatic hepatitis, aminotransferase elevations



Frequency not reported: Nervousness, irritability, sleeplessness (particularly in higher doses)

Nervous system


Frequency not reported: Dizziness, headache


Frequency not reported: Dizziness, tremor



Frequency not reported: Salicylate-induced variant angina, ventricular ectopy, conduction abnormalities, and hypotension, particularly during salicylate toxicity


Frequency not reported: Palpitations



Frequency not reported: Dehydration, hyperkalemia, hypoglycemia, sodium and fluid retention, respiratory alkalosis and metabolic acidosis (particularly during salicylate toxicity)



Frequency not reported: Interstitial nephritis, papillary necrosis, proteinuria


1. "Product Information. Bayer Aspirin (acetylsalicylsyra)." Bayer

2. Cerner Multum, Inc. "UK Summary of Product Characteristics."

3. "Multum Information Services, Inc. Expert Review Panel"

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.