Guarana Side Effects

Guarana seeds come from a shrub found in Brazil and Venezuela. These seeds contain more caffeine than coffee beans and can be made into beverages, pills and powders. The ingredient is often included in energy drinks, teas and diet pills. While some tout guarana's effectiveness for weight loss, this substance can cause side effects.

Common Side Effects`

• Common side effects of guarana include trouble sleeping, restlessness, increased heart rate, loss of appetite, anxiety, heart burn, shakiness, headaches, nausea, ringing in the ears, and frequent urination.

Allergic Reaction

• Signs of an allergic reaction to guarana include swelling of the throat, lips and tongue, hives or itchiness and trouble breathing Consult a doctor immediately if you are experiencing this side effects.

Serious Side Effects

• Serious side effects of guarana include vomiting, difficulty urinating, stomach cramps, racing heart, dizziness, seizures and severe stomach pain. These side effects may all indicate a guarana overdose and should be brought to the attention of a medical professional.

Other Conditions

• Side effects of guarana may be more dangerous to and more acutely felt by people with heart problems, high blood pressure, diabetes, kidney disease or an overactive thyroid. These people should avoid any beverage or medication with guarana. Guarana should also not be used by those with a caffeine allergy.

Other Medications

• People taking any other pills that contain ephedra will worsen any side effects caused by guarana and therefore the two should not be taken together. Side effects as severe as stroke, hemorrhage, myocardial infarction, and fatal changes in heart rate and blood pressure can occur when guarana and ephedra are combined.