Up to 400 mg of caffeine can be taken without a risk of toxicity. Although caffeine is an integral component of various drinks, it can cause side effects in some individuals even without high amount of caffeine. Common side effects of caffeine are: - Restlessness - Headache - Dizziness - Insomnia - Palpitations - Arrhythmias - Anxiety - Excess urination - Dependency Source: https://medlineplus.gov/caffeine.html Image via : https://www.nutraingredients.com/Article/2020/07/31/Caffeine-content-of-supplements-enough-to-exceed-safe-levels