Nicotine is best administrated through gum or a transdermal patch. I haven't heard of many people using it in pill form. Nicotine alone is similar to smoking a cigarette, but not identical: cigarettes also contain MAOI inhibitors which have synergistic effects with nicotine.

Just a minor correction, MAOI = MAO inhibitors. MAOI inhibitors is redundant.

Lozenges are also available.

It's interesting to note that apparently nicotine is not addictive without the MOAIs from tobacco smoke.