Everyone is sensitive to caffeine to one degree or another. The sensitivity to the substance is what causes it to affect the central nervous system, resulting in stimulation. Some people are more sensitive to caffeine than others, but if you develop severe symptoms after consuming the substance, you might have an allergy or consumed too much. Talk with your doctor about which symptoms are normal side effects and which are not.
The human body is sensitive to caffeine. It increases mental awareness and helps you stay awake longer. The substance is present in soda, tea, coffee, sports beverages, chocolate and certain medications. After you consume caffeine, the substance enters the bloodstream within minutes and affects your brain. A moderate dose of caffeine is about 200 to 300 milligrams daily. If you aren't accustomed to ingesting caffeine, you might experience a greater sensitivity than someone who consumes caffeine daily.
Common Side Effects
Some side effects of caffeine consumption are normal. Typical side effects include an increased heart rate, diarrhea, dizziness, nausea, vomiting, sleeping difficulty, tremors, irritability, jitters, nervousness and hyperglycemia, according to Drugs.com. The severity of these common side effects differs between individuals. If you’re more sensitive to caffeine than the average person, consider cutting back on your daily consumption.
If you develop severe symptoms from ingesting a small amount of caffeine, you might have an allergy. An allergic reaction to caffeine causes your immune system to overreact to any amount of caffeine. The immune system mistakes the substance as an intruder and creates a defense system that triggers immunoglobulin E antibodies, histamine and other chemicals. Common symptoms of an allergic reaction to caffeine include shortness of breath, hives, and facial, lip, throat or tongue swelling.
The more caffeine you ingest, the more likely you are to develop side effects. Drugs.com recommends not to consume more than 1,000 milligrams daily. If you suspect that you’ve overdosed on caffeine, seek immediate medical attention to prevent further complications. Signs of a caffeine overdose include vomiting, fever, dizziness, diarrhea, convulsions, confusion, hallucinations, change in alertness, irregular heartbeat, rapid heart rate, increased urination, muscle twitching and increased thirst, according to MedlinePlus.