Yeah, placebo and nocebo are future tense "I will please" "I will harm"

important note:

placebo is caused by a strong belief, even if logically you know it's not real it can still work

but

you first need the strong belief. how do you get such a strong belief? with a ritual of course. not necessarily one with bubbling cauldrons during the full moon (though if you believe in that kind of magic that'd work as well) but one that has you going to a place you associate with health, and talking to a person in a special outfit that you believe will fix you, then going to a secondary health place, and getting the health ~~potion~~ pills from someone in a special outfit. also called - going to a doctor and picking up meds from a pharmacy.

this entire process sets up the right environment for strongly believing you're going to feel better now, and then the sugar pills supercharged with placebo will work like magic.

they will also work if at some point either the doctor or the pharmacist whispers to you "btw that's just placebo". that's because the belief you've already established is much stronger than your logic

but if you just go out and buy tictacs at a gas station then chant to yourself "this will cure my headache this will cure my headache" it won't work, because you didn't have an opportunity to establish any emotional belief about them ie. you didn't manage to convince the emotional part of your brain that it'll work

this is also why homeopathy, essential oils, charging crystals, and other purely belief bases approaches work despite the thing itself not doing anything. the rituals surrounding those things simply manage to build a strong enough belief that causes the placebo effect

the same is true for the opposite - nocebo - if you strongly believe something is going to make you feel bad - it's going to

Most people believe red painkillers work better than other colours. Because of that when painkillers are tested, red ones work better (and red placebos also). You might find the placebo effect of red painkillers effective

I think caffeine also supresses certain kinds of headaches on its own, without the addiction. I had headaches before starting my caffeine habit and I also had them like half a year into quitting caffeine completely, and IME the caffeine definitely helps with them even when I wasn't years into a habit of drinking several cups of coffee every day.