2ml is supposed to translate to 24mg, which is a big dose. I do not believe any of the commercial patches go much past that. I asked Wedrifid, whose notes inspired my initial interest, and he was taking perhaps 2-4mg, and expressed astonishment that I might be taking 24mg. (2mg is in line with what I am told by another person - that 2mg was so much that they actually felt a little sick. On the other hand, in one study, the subjects could not reliably distinguish between 1mg and placebo25.) 24mg is particularly troubling in that I weigh ~68kg, and nicotine poisoning and the nicotine LD50 start, for me, at around 68mg of nicotine. (I reflected that the entire jar could be a useful murder weapon, although nicotine presumably would be caught in an autopsy’s toxicology screen; I later learned nicotine was an infamous weapon in the 1800s before any test was developed. It doesn’t seem used anymore, but there are still fatal accidents due to dissolved nicotine.) The upper end of the range, 10mg/kg or 680mg for me, is calculated based on experienced smokers. Something is wrong here - I can’t see why I would have nicotine tolerance comparable to a hardened smoker, inasmuch as my maximum prior exposure was second-hand smoke once in a blue moon. More likely is that either the syringe is misleading me or the seller NicVape sold me something more dilute than 12mg/ml. (I am sure that it’s not simply plain water; when I mix the drops with regular water, I can feel the propylene glycol burning as it goes down.) I would rather not accuse an established and apparently well-liked supplier of fraud, nor would I like to simply shrug and say I have a mysterious tolerance and must experiment with doses closer to the LD50, so the most likely problem is a problem with the syringe. The next day I altered the procedure to sucking up 8ml, squirting out enough fluid to move the meniscus down to 7ml, and then ejecting the rest back into the container. The result was another mild clean stimulation comparable to the previous 1ml days. The next step is to try a completely different measuring device, which doesn’t change either.

Ampakines bind to AMPARs to block uptake of glutamate, thereby increasing synaptic responses, and this has indeed been shown to minimize the effects of conditions such as Alzheimer’s. Ampakines are also being studied as possible treatments for schizophrenia, depression, ADHD and more. But there is a huge risk associated with ampakine consumption. They are now tightly regulated because if you exceed a safe dosage, you will begin to suffer neuronal damage from glutamate toxicity, which leads to some of the very conditions that ampakines are thought to attenuate. Ampakine consumption can also lead to a decrease in long-term synaptic depression (LTD), a process by which specific synapses (the space between neurons across which information is sent) are intentionally weakened in order to avoid a plateau in the efficiency of your synapses. In other words, it allows your neurons and their connections to continue growing in efficiency. LTD is believed to be necessary for healthy synaptic plasticity (the adaptability of synapses), memory function and motor skills. To be honest, there is debate over whether cognitive functions like motor learning are truly dependent upon LTD, but it is possible that if you were to take a higher-than-recommended dose of an ampakine, the overstimulation that would result may lead to suppressed LTD and consequently to poor memory and motor function.
There are many studies that suggest that Creatine helps in treating cognitive decline in individuals when combined with other therapies. It also helps people suffering from Parkinsons and Huntingtons disease. Though there are minimal side effects associated with creatine, pretty much like any nootropic, it is not  absolutely free of side-effects. An overdose of creatine can lead to gastrointestinal issues, weight gain, stress and anxiety.
The main concern with pharmaceutical drugs is adverse effects, which also apply to nootropics with undefined effects. Long-term safety evidence is typically unavailable for nootropics.[13] Racetams — piracetam and other compounds that are structurally related to piracetam — have few serious adverse effects and low toxicity, but there is little evidence that they enhance cognition in people having no cognitive impairments.[19]