What's the difference between a thaumaturgical ritual, requiring 30+ shifts, to give yourself supernatural might until the next sunrise (and also costing you 2 fate points), and just making a strength 10 potion that gives you might 10 until the next sunrise (for, 10 complexity?) Other than the 20+ points of complexity, not much...
What's the difference between a ritual (again, of 20+shifts) to give yourself cloak of shadows (the lowest refresh cost nightvision), or a 4 shift potion manuever "Can see in dark", either until sunrise? Again, other than the immense complexity difference (and the stealth bonus), not much.
So, as 20 complexity for this is stupid, but cheap powers aren't great for balance, I'd highly advise following the suggestions in the book on adding consequences. I'd make this a moderate physical consequence of "blinding migraine", that kicks in when the potion wears off.
So you can see in the dark, but the next day you kind of want to stay in the dark and your head is killing you.