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Diurex Side Effects

Generic name: caffeine / magnesium salicylate

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

Applies to caffeine/magnesium salicylate: oral tablet.

Nervous system

Nervous system side effects associated with caffeine consumption have included central nervous system stimulation such as irritability, restlessness, and jitteriness. Tinnitus and subjective hearing loss (or both) may occur with salicylate. Some investigators have reported that modest doses may result in decreased frequency selectivity and may therefore impair hearing performance, particularly in the setting of background noise.[Ref]


Gastrointestinal side effects of both caffeine and salicylate have included epigastric distress, abdominal discomfort or pain, nausea, and vomiting.[Ref]


Other side effects have included Reye's syndrome with salicylate use in children with an acute viral illness. Reye's syndrome has also been reported even more rarely in adults.[Ref]


Cardiovascular side effects associated with caffeine products have rarely included tachycardia, increased left ventricular output, and increased stroke volume.[Ref]


In general, consumption of higher doses of caffeine (less than 600 mg/day) has been reported to have lead to caffeinism. Caffeinism is a syndrome characterized by anxiety, restlessness, and sleep disorders (similar to anxiety states). It has also been reported that chronic, heavy caffeine ingestion may be associated with depression. Caffeine may cause anxiety and panic in panic disorder patients and may aggravate premenstrual syndrome (PMS).[Ref]


Renal side effects associated with caffeine consumption have included increased urine flow rate, creatinine clearance, and sodium and calcium excretion.[Ref]


Respiratory side effects of salicylates have included bronchospastic reactions. Nonacetylated salicylates rarely cause reactions even in susceptible people when very large doses are given.


Hypersensitivity side effects of magnesium salicylate include severe allergic reactions which may include hives, facial swelling, asthma, and shock.

More about Diurex (caffeine / magnesium salicylate)

Other formulations

Related treatment guides


1. Boettcher FA, Salvi RJ (1991) "Salicylate ototoxicity: review and synthesis." Am J Otolaryngol, 12, p. 33-47

2. (2001) "Product Information. Cafcit (caffeine)." Roxane Laboratories Inc

3. Lanas A, Serrano P, Bajador E, Esteva F, Benito R, Sainz R (1997) "Evidence of aspirin use in both upper and lower gastrointestinal perforation." Gastroenterology, 112, p. 683-9

4. Thomas J, Straus WL, Bloom BS (2002) "Over-the-counter nonsteroidal anti-inflammatory drugs and risk of gastrointestinal symptoms." Am J Gastroenterol, 97, p. 2215-9

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

6. Belay ED, Bresee JS, Holman RC, Khan AS, Shahriari A, Schonberger LB (1999) "Reye's syndrome in the United States from 1981 through 1997." N Engl J Med, 340, p. 1377-82

7. Sondermeijer H, van Marle A, Kamen P, Krum H (2002) "Acute effects of caffeine on heart rate variability." Am J Cardiol, 90, p. 906

8. Hartley TR, Lovallo WR, Whitsett TL (2004) "Cardiovascular effects of caffeine in men and women." Am J Cardiol, 93, p. 1022-6

9. Clementz GL, Dailey JW (1988) "Psychotropic effects of caffeine." Am Fam Physician, 37, p. 167-72

10. Sawynok J (1995) "Pharmacological rationale for the clinical use of caffeine." Drugs, 49, p. 37-50

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.