Skip to main content

Caffeine / sodium benzoate Side Effects

Medically reviewed by Last updated on Sep 1, 2022.

Applies to caffeine / sodium benzoate: injection solution.

Serious side effects

Along with its needed effects, caffeine/sodium benzoate may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking caffeine / sodium benzoate:

Incidence not known

  • Extra heartbeats
  • fast, pounding, or irregular heartbeat or pulse
  • trembling or shaking of the hands or feet

Get emergency help immediately if any of the following symptoms of overdose occur while taking caffeine / sodium benzoate:

Symptoms of overdose

  • Chest pain or discomfort
  • confusion
  • confusion as to time, place, or person
  • decreased urination
  • dizziness
  • dry mouth
  • fainting
  • fever
  • hallucinations
  • holding false beliefs that cannot be changed by fact
  • increase in heart rate
  • lightheadedness
  • pounding or rapid pulse
  • rapid breathing
  • sleeplessness
  • slow heartbeat
  • sunken eyes
  • thirst
  • trouble sleeping
  • unable to sleep
  • unusual excitement, nervousness, or restlessness
  • unusual tiredness or weakness
  • wrinkled skin

Other side effects

Some side effects of caffeine / sodium benzoate may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

  • Anxiety
  • continuing ringing or buzzing or other unexplained noise in the ears
  • headache
  • hearing loss
  • hyperventilation
  • increased sensitivity to pain
  • increased sensitivity to touch
  • irritability
  • restlessness
  • shortness of breath
  • tingling in the hands and feet
  • trouble sleeping

For Healthcare Professionals

Applies to caffeine / sodium benzoate: injectable solution.


Large doses of caffeine may cause headache, excitement, agitation, scintillating scotoma, hyperesthesia, tinnitus, muscle tremors or twitches, diuresis, tachycardia, extrasystoles, other cardiac arrhythmias, and a condition resembling anxiety neurosis.[Ref]

More about caffeine / sodium benzoate

Patient resources

Professional resources

Related treatment guides


1. "Product Information. Caffeine-Sodium Benzoate (caffeine-sodium benzoate)." American Regent Laboratories Inc (2004):

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.