3 doctors weighed in:

After how many hours are the nodoz (caffeine) going to wear off?

3 doctors weighed in
Dr. R Sangal
Internal Medicine - Sleep Medicine
2 doctors agree

In brief: Half-life 5-6 hours

The half-life of caffeine is 5-6 hours, which means the amount in your blood (and therefore the effect) decreases by half in 5-6 hours.
How long it works will depend not just on the half-life but also on the dose taken.

In brief: Half-life 5-6 hours

The half-life of caffeine is 5-6 hours, which means the amount in your blood (and therefore the effect) decreases by half in 5-6 hours.
How long it works will depend not just on the half-life but also on the dose taken.
Dr. R Sangal
Dr. R Sangal
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Dr. Heidi Fowler
Psychiatry

In brief: Manufacturer info:

"With different ages, sizes, and caffeine tolerance, the time that it takes for No-Doz to begin affecting you and the time No-Doz will remain in your system varies.
On average, it can take 10 to 30 minutes to begin and the effect lasts for at least 3 hours and may in some cases last much longer." http://www.nodoz.com.au/faq.php

In brief: Manufacturer info:

"With different ages, sizes, and caffeine tolerance, the time that it takes for No-Doz to begin affecting you and the time No-Doz will remain in your system varies.
On average, it can take 10 to 30 minutes to begin and the effect lasts for at least 3 hours and may in some cases last much longer." http://www.nodoz.com.au/faq.php
Dr. Heidi Fowler
Dr. Heidi Fowler
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