I’ve been trying modafinil over the past two months.
I do not know enough science about it to discuss it from that angle. All I want to do is detail my own experience with it.
First off, there is a noticeable improvement in thinking. It’s hard to pin down. More patience, more concentration, more desire to do work, to write, to read, to think. It’s similar to caffeine in that way. It lasts longer than caffeine.
Second, it prevents sleep. This is unsurprising, since it is used to treat narcolepsy. Narcolepsy is a sleep disorder; the sufferer falls asleep unpredictably and suddenly at any time of day. If I take 50 mg of modafinil after lunch, I will be up way past my bedtime.
Speaking of mg, at first I tried 50 mg, then 100. I like the 100 mg dose, but of course it has more tendency to produce insomnia. I try to use it every second day, or every third.
A third effect is an improvement in my mood. It’s not prescribed for that and, from my reading, it does not do that for everybody. Anti-depressants (and anti-histamines) have mental effects that vary greatly from person to person. Often, the same drug that makes one person agitated, makes another person sleepy.
One downside of modafinil is that it does not mix well with alcohol. I haven’t experienced this, I just avoid mixing.
Another downside: sleep is important for your health. Stimulants that prevent normal sleep can be very dangerous. Fact: if you do not sleep, your brain will go insane after about 100 hours, until you sleep. Wealthy cocaine users often display this adorable trait (“Winning!”). You must be wealthy to get enough cocaine to have this effect. But ordinary folks can use meth instead and get just as crazy.
Modafinil is not exactly a stimulant. Stimulants increase our wakeful, active hormones (e.g., adrenaline). It is believed that modafinil does not do that, but instead, that it disrupts the mechanism in your brain that leads to sleep.
But the loss of sleep is just as much a problem. It does not matter whether it is due to crank, coke, modafinil, the Late Show, or a hot young girlfriend. Health and alertness depend on sleep, especially alertness.