angellore:

If you get (what you may think is) seasonal depression but during the summer instead of during winter, check for symptoms of dysautonomia.

For a lot of people with dysautonomic disorders (POTS included) hot environments are hell, as the warmth makes our blood vessels dilate even more than they already inadequately do. This goes x2 if the hot environment you’re in is humid rather than dry and things such as hot showers and saunas make you dizzy or tired (nothing worse for us than humid heat).

This happens because too dilated blood vessels may make your blood pressure low or unstable, which in turn means your upper body is deprived of enough oxygen (your blood is pooling down in your feet instead of being pushed upwards thanks to more constricted blood vessels). Most worryingly, our brains are being deprived of enough oxygen.

An oxygen deprived brain, especially if deprived of it persistently through time, causes chronic fatigue and brain fog, two symptoms often misdiagnosed as depression, since you have no energy to even think, focus or have good memory (brain fog), much less to be active, experience pleasure/enjoyment, or be motivated. It can also reduce sex drive, among many other things.

On top of that, experiencing chronic fatigue and brain fog is very likely to make you genuinely depressed, because it’s very debilitating, confusing, emotionally miserable and hard to combat.