The amount of cotinine in your urine will vary depending on the amount and frequency of nicotine use. On average, nicotine ...

And nicotine really is addictive. The dopamine it stimulates, particularly in a brain area called the nucleus accumbens, ...

Nicotine itself could clear from your body in a few hours, but its byproduct can linger for days or weeks. Most nicotine tests detect cotinine, which can show up in urine, saliva, blood, hair, and ...

Whether you're smoking cigarettes or vaping e-cigarettes, you're ingesting nicotine. Either way, the addictive substance is linked to a host of health issues, and experts say they still don't have a ...

It may feel like smoking helps you stay awake after a sleepless night, but that false alertness comes from a surge of ...