Nicotine is not a narcotic. The use of "narcotic" as a synonym for "illegal drug" is a side-effect of the verbage in U.S. and other national drug laws. But, it is not scientifically accurate. (In fact, nicotine isn't even a narcotic under U.S. drug law. If it were, it's use would be illegal without medical necessity.)
Discounting the original meaning that is derived from Greek (which is "anything that causes sleepiness") in contemporary usage narcotics are derived from the opium poppy, or are close synthetic analogues that work on the same receptors. Instead nicotine works on a subset of adrenergic receptors called, appropriately enough, nicotinic receptors.
Narcotics:
Opium
Morphine
Heroin
Fenatanyl
Codeine
Oxycodone
Hydrocodone
Meperedine
Not Narcotics:
Cocaine
Nicotine
LSD
Marijuana
Aspirin
Tylenol
Motrin
Nicotine
Asparagus :-)
I'll buy the "extremely toxic" part, with some migitaion:
About 50 milligrams of nicotine is a fatal dose for an adult human, so it is an amazingly potent poison. Spilling liquid nicotine on exposed skin is a fatal event. Injecting the amount of nicotine in a cigar or pack of cigarettes intravenously, or even swallowing it in pure form, would also be fatal. However, in the doses and manner that it is typically administered recreationally it is merely a powerful stimulant.
But nicotine is not especially carcinogenic- it is the other stuff in tobacco that causes cancer. Likewise regarding emphysema (a.k.a. COPD) and other repiratory ailments.
Nicotine is, as you said, one of the most addictive substances known to man.
P.S.
Sorry. I'm a doctor. I could do this all day. And if I were given the power to wipe one substance from the face of the Earth it would be a tough call between tobacco and alcohol.