If one inhales cigarette smoke after a period of abstinence, what causes the almost immediate “rush” of dizzyness etc?
Anoxia.
Carbon Monoxide displaces the Oxygen in your blood.
Cite?
One does not habituate to carbon monoxide; it’s a poison, period.
Nicotine is a drug, and one habituates to it; after abstaining, one is subject to the same effects as when one first started smoking. I have smoked a few cigarettes, and I remember the dizzying head rush from the nicotine – carbon monoxide does NOT have the same effect.
I smoke a pipe and do not inhale the smoke, but I get a definite intoxicant effect. In ADDITION, the intoxication strength varies greatly depending upon which high-falutin’ blend I smoke. Is it being claimed that some tobacco blends give off significantly more or less CO than do others?
I am an occasional user of Red Man and other smokeless full-leaf tobacco products (I rarely smoke: maybe two or three cigs a month). As a non-smoker, I know all about the rush that you get, and it’s definately not from the carbon monoxide, and definately is from the drug content of the tobacco.
Ah, disgusting unhealthy habits…
It’s not oxygen deprivation, I don’t believe. The same thing happens when you chew tobacco (in fact, its much more noticeable when you chew tobacco), and carbon monoxide is a product of burning plant matter.
Well, I worship frequently at the altar of Turkish Golds, and I never get that head rush any more, even if I have too many and end up feeling kind of gross, no dizzyness or anything. I definitely feel a very tangible rush, though, sort of an immediate “all is right with the world” feeling; I loosen up and my concentration improves (I smoke while doing homework, it helps!).
I also frequent a place here in Austin that will bring a hookah to your table with some flavored tobacco in it, and that stuff has interesting effects. Non-smokers find it very mild and easy to smoke, and they do not get a headrush or nausea from it. Smokers and non-smokers alike get VERY chilled out, regardless of nicotine tolerance. All is extremely right with the world, man. And yes, it IS tobacco in the hookah. 
LC
Nicotine-Induced Limbic Cortical Activation
in the Human Brain: A Functional MRI Study
Inhaled nicotine gets to the brain in <15 seconds.