Tylenol (acetaminophen) typically starts working within the following time frames depending on the formulation:
- Oral tablets and extended-release tablets: about 30 to 45 minutes to start working
- Orally disintegrating tablets and liquid forms: around 20 minutes
- Intravenous acetaminophen: 5 to 10 minutes, with peak concentration reached about 30 minutes after infusion begins
- Effervescent forms (not common as single-ingredient Tylenol in the U.S.): onset around 20 minutes, faster than regular tablets which take about 45 minutes
- Acetaminophen suppositories (rectal): slower onset, taking about 3 hours to reach maximum effect
Tylenol generally provides pain relief for about 4 to 6 hours after a dose
. Taking it on an empty stomach may speed absorption and onset, while food can delay it. In summary, if you take standard oral Tylenol tablets, expect pain relief to begin within 30 to 45 minutes, with faster onset for liquids or disintegrating forms and much faster onset with intravenous administration. The effect typically lasts several hours
