If you've ever tried nicotine you'll quickly understand why caffeine could never substitute for it. Sure, they're both stimulants. But nicotine decreases anxiety. Caffeine increases it.
Actually, they both do the same thing, but attack different sides of the mood slope.
Which you'd know, if you ever stopped to consider how to adjust your mood with either.
Caffeine introduces anxiety and irritability on downslope, after about two half-lives, or 12-ish hours (6 hour half life). On the up slope, caffeine provides a long slowly declining period of alertness and performance. The initial buzz comes on strong and tapers off over time.
People seek caffeine to perform. But a slow sinking feeling appears near the end of the day.
Nicotine modifies mood on the other side of the bend, with it's presence evening out irritability with immediate relief. The trail off goes unnoticed until a sudden urge kicks in, to bump one's self back up onto the plateau.
Nicotine is sought to cure or cool an immediate pang, which leaves the impression of easing into relaxation, which degrades silently until suddenly noticed as an urge to re-up.
The perception of nicotine is downtime, even though the dosage process and serum curve is the usual spike and tapered downslope, people learn modify the nicotine downslope differently, by catching the drop-off before cravings become desperate.
Which is why cigarettes are designed as they are, and achieve product success the way they do. Metering doses at an almost hourly rate, with twenty dose packs marketed to afford exactly that behavior.
Coffee, as a liquid, is readily either sipped or chugged as needed, and has different preparation and consumption habits, so its marketing is different.
Caffeine's downslope is handled differently, since the withdrawal effects, are separated by longer distances of up to 48 hours, and because circadian rhythms are more drastically effected. Consuming in the late afternoon results in insomnia, so the better choice is to cure the anxious late day mood disruptions with food and alcohol, and stave off withdrawal (vasodilation migraines, etc) the next morning.
I use both regularly. I never notice the "downslope" of caffeine, although maybe that's my tolerance.
The neurology is totally different. Caffeine primarily affects the heart rate via adenosine (A1R) antagonism. Nicotine binds to the ion channel nAChR which is expressed all over the brain and the nervous system. Full agonists of nAChR cause convulsive seizures, while antagonists are paralytic, but nicotine is a partial agonist, producing a sort of stability.
That's why nicotine is anxiolytic: it interferes with spikes and droughts of acetylcholine, smoothing the highs and lows of neural activation. The brain responds by "sensitizing", changing acetylcholine more dramatically in response to stimuli, and increasing the density of nACh receptors. That's why nicotine withdrawal is so awful: every mood is enhanced and you can't calm down.
By contrast, caffeine, which primarily affects the A1 receptors that are expressed in cardiac neurons and smooth muscle tissue, is obviously never anxiolytic. A faster heartbeat does not produce calmness. The faster heartbeat increases the availability of energy in the brain and muscle, producing wakefulness. It has some other effects in the brain, particularly the basal forebrain, where inhibiting A1 also promotes wakefulness, but the cardiac effects of A1 dominate its practical effects to the extent that A1 agonists (opposite of caffeine) have never been implemented as sedatives because of their tendency to produce life-threatening drops in heart rate and blood pressure.
You'd think, having studied this so much, I'd be more responsible, but humans are a funny animal. Anyway, there's no way a pure stimulant is going to substitute for an anxiolytic that takes effect in ten seconds. It makes sense in zero realities.
Which you'd know, if you ever stopped to consider how to adjust your mood with either.
Caffeine introduces anxiety and irritability on downslope, after about two half-lives, or 12-ish hours (6 hour half life). On the up slope, caffeine provides a long slowly declining period of alertness and performance. The initial buzz comes on strong and tapers off over time.
People seek caffeine to perform. But a slow sinking feeling appears near the end of the day.
Nicotine modifies mood on the other side of the bend, with it's presence evening out irritability with immediate relief. The trail off goes unnoticed until a sudden urge kicks in, to bump one's self back up onto the plateau.
Nicotine is sought to cure or cool an immediate pang, which leaves the impression of easing into relaxation, which degrades silently until suddenly noticed as an urge to re-up.
The perception of nicotine is downtime, even though the dosage process and serum curve is the usual spike and tapered downslope, people learn modify the nicotine downslope differently, by catching the drop-off before cravings become desperate.
Which is why cigarettes are designed as they are, and achieve product success the way they do. Metering doses at an almost hourly rate, with twenty dose packs marketed to afford exactly that behavior.
Coffee, as a liquid, is readily either sipped or chugged as needed, and has different preparation and consumption habits, so its marketing is different.
Caffeine's downslope is handled differently, since the withdrawal effects, are separated by longer distances of up to 48 hours, and because circadian rhythms are more drastically effected. Consuming in the late afternoon results in insomnia, so the better choice is to cure the anxious late day mood disruptions with food and alcohol, and stave off withdrawal (vasodilation migraines, etc) the next morning.