It Works Greens contains several ingredients, such as magnesium and potassium, that may cause side effects such as stomach upset and vomiting, according to Amazon.com and WebMD. However, the supplement's manufacturer does not indicate that the product has any side effects.
Potassium is usually safe for most people, but it can cause symptoms such as nausea, diarrhea and intestinal gas, notes WebMD. Taking too much potassium can result in feelings of burning, tingling, weakness, dizziness, paralysis and an irregular heartbeat. High doses can also cause metal confusion and death. People who have certain digestive disorders should avoid taking potassium supplements because they can lead to excess potassium in the body.
Magnesium can cause nausea, vomiting, diarrhea and stomach upset in some people, explains WebMD. When taken in high amounts, serious side effects such as low blood pressure, confusion, coma and death can occur. Other side effects from high doses include irregular heart rhythm and slowed breathing. People with bleeding disorders may have an increased risk of bleeding or bruising when taking magnesium because it slows blood clotting. People with kidney problems or those who have heart blockage should avoid taking too much magnesium because it can worsen their symptoms.
Consult a doctor if you are taking any medications because It Works Greens may produce adverse interactions, according to Supplement Geek. Because the ingredients in It Works Greens have blood thinning properties, users should not take the supplement for at least two weeks before surgery to reduce the risk of complications.