Is there a nasal spray to stop smoking?

Yes: there are a variety of kinds of nicotine replacement therapy. The best known are the skin patch and nicotine gum. However, there are also lozenges and nasal sprays which contain nicotine, and can be used to reduce the symptoms of nicotine withdrawal. Pills, such as bupropion (Zyban or Wellbutrin) and varenicline (Chantix) can also be helpful, together with a formal smoking cessation program.