The idea of taking a pill to cure a disease did exist; it would’ve been called a “specific.” Pills were handmade but were fairly common based on what I’ve seen, although cordials, electuaries, and other drinkables predominated.
"or even a stimulant at all"
Its strange that tea was thought of as a stimulant but not coffee?! I could drink 10 cups of tea, and only feel the urge to wee. That much coffee and I'd be up the wall!
But then the Victorians were shooting up opiates whilst warning of the dangers of alcohol so I suppose there is a lot of 'cultural conditioning' going on there (and here).
This just looks like evidence that you don't drink tea and don't know what's in it, or that you've confused herbal tea with tea from the tea plant. Tea seems to have about half the amount of caffeine coffee does. For example, here are figures from the Mayo Clinic:
https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-h...
Coffee is more of a stimulant than tea, but tea is still very strong, so it's unsurprising that the British were aware of its effects. If you're trying to stay awake, tea will do the job.
> The whole of the day's tea would be brewed in the morning, taxed by a visiting excise officer, and then kept in barrels and reheated as necessary throughout the rest of the day.
If I was a coffeehouse owner, I would brew that tea for a long time to get as concentrated a drink out of it as possible.
[0] https://en.wikipedia.org/wiki/Gongfu_tea_ceremony