The severity and length of a hangover carries so many variables, so it's hard to say how long a hangover could last.
According to Johns Hopkins Medicine: “Hangovers can last up to 72 hours after drinking, but most are shorter in duration. Again it depends on how much was consumed, how dehydrated you became, nutritional status, ethnicity, gender, the state of your liver, medications, etc”
For most people, hangovers typically go away within 24 hours but even that can feel like an eternity when you’re dealing nausea, headaches, fatigue and stomach sickness.
To get more scientific, hangover symptoms peak when the blood alcohol concentration in the body returns to about zero.
And remember, there is no magic cure for a hangover. But there are ways you help the fuzzy head the next morning, find out more here: Is there a cure for Hangovers? How do you prevent being hungover?
Please note: Intended for educational and informative purposes only and not intended to serve as medical or professional advice. For medical attention or advice you should consult your physician or other health care professional.