While relatively safe and side effects are uncommon, Longevinex is not totally without side effects.
Longevinex should not be taken if anemic. Symptoms may include fatigue, leg cramps in bed at night, and frontal headaches.

Longevinex may induce Achilles heel soreness (tendonitis) if your diet is deficient in copper. If this occurs, cease taking Longevinex for a time and consume foods that provide copper, such as nuts and cocoa. Supplemental magnesium and vitamin C are also recommended if this occurs.

You may take too many supplements containing polyphenols that bind to minerals such as copper.

Take with meals to reduce the chance of gastric side effects. Ingredients in Longevinex may induce symptoms of skin rash, anxiety, stiff hands, and flu-like symptoms. Cease taking if this occurs.

Excessive consumption of polyphenols (bioflavonoids) like those provided in Longevinex (quercetin, resveratrol, ferulic acid, grape seed, green tea, curcumin, coffee bean, turmeric, milk thistle, cinnamon, may inhibit an enzyme that keeps a lid on adrenal stress hormones, which can then result in symptoms of anxiety, panic attacks, sleeplessness, hunger, high blood pressure, and heart palpitations. Cease taking Longevinex if symptoms like these occur, and evaluate your total consumption of polyphenols from your diet and supplements.