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Monster Energy (473ml / 16oz)

Caffeine Half-Life Analysis

For: Elderly (65+)
160
mg Caffeine
6.5
Hour Half-Life
~5
Hours to Sleep-Safe
300
mg Daily Limit
bedtime
To sleep well at 10 PM, stop caffeine by:
5:35 PM

trending_down Caffeine Decay Timeline

How 160mg caffeine clears from your system with a 6.5-hour half-life

Time Elapsed Caffeine Remaining % of Original Status
Now (consumption) 160.0 mg
100.0% 		Active
After 1 hour 143.8 mg
89.9% 		Active
After 2 hours 129.3 mg
80.8% 		Active
After 3 hours 116.2 mg
72.6% 		Active
After 4 hours 104.4 mg
65.3% 		Active
After 5 hours 93.9 mg
58.7% 		Moderate
After 6 hours 84.4 mg
52.7% 		Moderate
After 8 hours 68.2 mg
42.6% 		Moderate
After 10 hours 55.1 mg
34.4% 		Moderate
After 12 hours 44.5 mg
27.8% 		Minimal
After 16 hours 29.0 mg
18.2% 		Minimal
After 20 hours 19.0 mg
11.9% 		Minimal
After 24 hours 12.4 mg
7.7% 		Minimal

health_and_safety Health Insights for Elderly (65+)

⚠️ Important Health Consideration

After age 65, liver enzyme efficiency decreases, extending caffeine's half-life. Sensitivity to caffeine's effects on sleep also increases.

Daily Limit Calculation

  • • Recommended daily limit: 400mg of caffeine
  • • Caffeine per serving: 160mg
  • • Servings until limit: 2.5 servings

Avoid caffeine after midday. Consider reducing total intake as sensitivity increases.

Sleep Quality Impact

Caffeine blocks adenosine receptors in the brain, preventing the buildup of sleep pressure. Even when you don't feel "wired," residual caffeine can reduce deep sleep quality by up to 20%.

>100mg
May disrupt sleep
50-100mg
Reduced deep sleep
<50mg
Minimal impact

science How Caffeine Half-Life Works

Half-life is the time required for the body to eliminate 50% of a substance. For caffeine, this primarily occurs in the liver through the CYP1A2 enzyme system.

With a half-life of 6.5 hours for elderly (65+), caffeine follows exponential decay:

  • After 6.5 hours: 50% remains (80.0mg)
  • After 13.0 hours: 25% remains (40.0mg)
  • After 19.5 hours: 12.5% remains (20.0mg)
  • After 26.0 hours: 6.25% remains (10.0mg)

The elderly (65+) category has a slower metabolism compared to healthy adults (5 hours baseline). After age 65, liver enzyme efficiency decreases, extending caffeine's half-life. Sensitivity to caffeine's effects on sleep also increases.

warning Please Note

Avoid caffeine after midday. Consider reducing total intake as sensitivity increases.

Compare Other Drinks

Brewed Coffee (240ml / 8oz) 95mg Espresso (30ml / 1oz shot) 63mg Red Bull (250ml / 8.4oz) 80mg Green Tea (240ml / 8oz) 28mg

Compare Conditions

Healthy Adult 5.0h Smokers 3.0h Pregnancy 10.5h Birth Control Users 7.5h Liver Impairment 12.0h Fast Metabolizers (Genetic) 3.5h

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About Monster Energy (473ml / 16oz)

Large format energy drink

Note: One can contains nearly the recommended daily limit

help Frequently Asked Questions

How long does Monster Energy (473ml / 16oz) caffeine last for elderly (65+)?

For elderly (65+), the caffeine half-life is approximately 6.5 hours. This means that 160mg of caffeine from Monster Energy (473ml / 16oz) will take about 6.5 hours to reduce to 80mg, and 13.0 hours to drop to 40mg. Full clearance (below 10mg) takes approximately 26.0 hours.

When should I stop drinking Monster Energy (473ml / 16oz) to sleep well?

If you plan to sleep at 10 PM, you should consume your last Monster Energy (473ml / 16oz) by 5:35 PM. This allows approximately 4.4 hours for caffeine levels to drop below the sleep disruption threshold of 100mg.

How does being in the 'Elderly (65+)' category affect caffeine metabolism?

After age 65, liver enzyme efficiency decreases, extending caffeine's half-life. Sensitivity to caffeine's effects on sleep also increases. Avoid caffeine after midday. Consider reducing total intake as sensitivity increases.