A 380 ml bottle of Lucozade Energy Original carries 46 mg of caffeine, already under the 50 mg threshold where most people can fall asleep normally, so one serving needs no cutoff time. Multiple servings still stack: the median caffeine half-life is 5 hours.
Lucozade Energy Original Last-Call Times by Bedtime
Latest time to finish a 380 ml bottle of Lucozade Energy Original (46 mg of caffeine) and still be under 50 mg of residual caffeine at bedtime, assuming the median 5-hour half-life. Your personal half-life may sit anywhere in the 2 to 12 hour range.
| Bedtime | Last call for Lucozade Energy Original | Residual at bedtime |
|---|---|---|
| 9:00 PM (21:00) | Any time | 46 mg (already under 50 mg) |
| 10:00 PM (22:00) | Any time | 46 mg (already under 50 mg) |
| 11:00 PM (23:00) | Any time | 46 mg (already under 50 mg) |
| 12:00 AM (00:00, midnight) | Any time | 46 mg (already under 50 mg) |
Clearance Time by Serving Size
How long each serving of Lucozade Energy Original needs before bed to drop under 50 mg:
| Serving | Caffeine | Time needed before bed |
|---|---|---|
| 380 ml bottle | 46 mg | No wait needed |
| 500 ml bottle | 60 mg | 1 h 19 min |
Source: caffeine figures from Lucozade official FAQ, accessed 2026-06-11. Values can vary by batch, location, and preparation; check the label or the source for the latest figures.
How the Math Works
With 46 mg per 380 ml bottle, a single serving of Lucozade Energy Original never crosses the 50 mg threshold where caffeine measurably delays sleep for most people, so there is no last-call time to respect for one serving. That changes when servings stack: caffeine decays exponentially with a median 5-hour half-life, so two or three servings through the afternoon and evening can still leave more than 50 mg in your system at bedtime.
Individual half-lives also run from about 2 to 12 hours depending on CYP1A2 genetics, medications, smoking, and pregnancy. If you are caffeine-sensitive or drinking multiple servings, model your real intake in the caffeine half-life calculator.