How does tolerance to nicotine develop?

Tolerance to nicotine develops as the brain and body adapt to its presence over time. Regular exposure to nicotine leads to changes in neurotransmitter systems, particularly the upregulation of nicotinic acetylcholine receptors, which reduces the drug's stimulating effects. Consequently, users require larger doses to achieve the same effects initially experienced, leading to increased consumption. This biological adaptation, combined with psychological factors, contributes to the addictive nature of nicotine.