I took Modafinil. You can read other reviews from PillScout and Examine for some background on the drug, but I wanted to see if it would materially alter my productivity at work. For my first experience, I took 1/2 of a 200mg pill, which is half the typical dosage. Here are the effects I noticed:
Increased attention - It was easier to concentrate on work, especially tasks of a non-creative nature (e.g. creating Excel spreadsheets). I did not have the same compulsion to check Facebook, look at my RSS feeds, or otherwise goof around while I was attempted to get something done.
Tunnel vision - I could stop myself from focusing on one thing if I tried, but intense focus came much more naturally.
Lack of social outgoing - In my previous experience with stimulants (mostly amphetamines), I noticed that they made me significantly more outgoing and genuinely intellectually curious. On Modafinil, I felt even less outgoing than usual.
Lack of euphoria - Prior stimulants have given me this effect and I did not notice it at all on modafinil. On the contrary, it gave me a grim, almost depressed focus on the task at hand.
Dry mouth - Mild.
Reduced appetite - Studies confirm this, though the drug is not associated with long-term weight loss.
The drug made me more focused but it did not make me more creative. The overall effects were fairly mild, which is to be expected from only taking half the typical dose. Doing the drug isn't particularly pleasurable, unlike like having a lot of coffee or taking a time release Adderall pill, but I could see it improving alertness and attention enough to get work done. I am typically well-rested at work, so I cannot comment on its ability to improve cognition when already fatigued.
I did feel a low-level of dread throughout the day even though I was not objectively having a bad day, which discourages me from using the drug on a regular basis. Perhaps Modafinil's method of action on neurotransmitters suggests caution for those prone to depression or anxiety. I have not had those problems in several years, but the background mood felt similar to mild depression. Some poking around on the internet suggests that it has been used to treat depression, so I won't say my experience is typical. I may try it again with the full dosage just to see what happens.
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