We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Here’s our process. How long does nicotine last? Whenever you smoke or chew tobacco, or inhale secondhand smoke from a cigarette, nicotine is absorbed into your bloodstream. From there, enzymes in your liver break most of the nicotine down to become cotinine. The amount of cotinine will be proportionate to the amount of nicotine you ingested. These substances are eventually eliminated through your kidneys as urine. Cotinine, nicotine’s main breakdown product, can usually be detected in your body for up to three months after ingestion. How long it stays in your syste... [Read more]