From the Research
Muscle twitching can occur within 15-45 minutes after ingesting 800 mg of caffeine, which is an excessive and potentially dangerous dose. This amount exceeds the FDA's recommended daily limit of 400 mg and may cause significant side effects, as noted in a case report of caffeine toxicity 1. Caffeine stimulates the central nervous system and increases neurotransmitter release, leading to heightened nerve activity that can manifest as muscle twitches, tremors, and jitteriness. Other symptoms at this high dose may include rapid heartbeat, anxiety, insomnia, digestive issues, and in severe cases, heart palpitations or cardiac arrhythmias.
The exact timeline varies based on individual factors like body weight, metabolism, caffeine tolerance, and whether food was consumed with the caffeine. A study on the effects of low doses of caffeine on human performance and mood found that even small doses of caffeine can have significant effects on the body 2. However, the study that is most relevant to this question is the one that discusses the effects of high doses of caffeine, which can be toxic 1.
Some key points to consider when evaluating the effects of caffeine include:
- The dose of 800 mg is extremely high and can cause severe side effects
- Individual factors like body weight and metabolism can affect the timeline of muscle twitching
- Caffeine can interact with other substances, such as benzodiazepines, and affect their efficacy 3, 4
- The FDA's recommended daily limit of 400 mg should not be exceeded to avoid potential toxicity 1
Anyone experiencing concerning symptoms after high caffeine consumption should seek immediate medical attention, as 800 mg approaches levels that could cause caffeine toxicity in some individuals. It is essential to prioritize caution when consuming caffeine and to be aware of the potential risks associated with high doses.