Medicinals

Everything about Qat/Khat/Kat - Edmund Burton
Bolus for Ague - Deborah Lysaght
Tea and Honey for a Cold - Doug Essenger-Hileman
Goddard's Drops - Charlezzzzz Muñoz
Seasickness
             Tim Elliot
             Gretchen Mini
             Martin Watts

Everything about Qat/Khat/Kat - Edmund Burton
Treason's Harbor, p. 182 (Norton)
"'We are chewing khat,' said Stephen, holding up a green twig."
According to this page, it has nothing to do with marijuana, being instead a sort of herbal amphetamine:
Everything about Qat/khat/kat
"KHAT (KAT) Because khat contains ephedrinelike compounds it seems best included in this section [a section on Amphetamines]. Lewin (1931) gave a brief account of khat and how it was used. Apparently it was taken socially to produce excitation, banish sleep, and promote communication. It was used as a stimulant to dispel feelings of hunger and fatigue.
"The natives chewed young buds and fresh leaves of catha edulis (Celastrus edulis). This is a large shrub which can grow to tree size. It originated in Ethiopia and spread until its use covered Kenya, Nyasaland [now Malawi], Uganda, Tanganyika [now Tanzania], Arabia, the Congo, Rhodesia [now Zimbabwe and Zambia], and South Africa. The khat trees are grown interspersed between coffee trees.
"Khat was used in Yemen even before coffee and it was immensely popular. Lewin described khat markets to which khat was brought in bundles of branches from the mountains.
"Khat contains cathine (d-norisoephedrine), cathidine, and cathinine. Cathine is also one of the alkaloids found in Ephedra vulgaris. It is fortunate, perhaps, that khat is also very rich in ascorbic acid which is an excellent antidote to amphetamine-type compounds....."

Bolus for Ague - Deborah Lysaght
Two ounces of the best Peruvian bark, finely powdered, may be divided into twenty-four doses. These may either be made into boluses, as they are used, with a little syrup of lemon, or mixed in a glass of red wine, a cup of camomile tea, water-gruel, or any other drink that is more agreeable to the patient. It has lately been observed, that the red bark is more powerful than that which has for some time been in common use. Its superior efficacy seems to arise from its being of a more perfect growth than the quill bark, and consequently more fully impregnated with the medical properties of the plant.

Tea and Honey for a Cold - Doug Essenger-Hileman
While I would never put lemon and cream together, I certainly put lemon and honey together. In fact, when I have a cold, a mug of store-brand tea-bag tea with lemon and honey is one of my comfort foods.

Goddard's Drops - Charlezzzzz Muñoz
Pepys, an early member of the Royal Academy (he eventually became president) dined, one evening in 1655, with Dr Goddard, a fellow member who had once been physician to Oliver Cromwell.
It's interesting to imagine what Maturin (a later member) wd have thought about Goddard's Drops, wch were prescribed for King Charles in an effort to cure his lethargy, and I wish some lazy Lissun wd make up a batch, take a course of them, and report to us. Do they work?
The ingredients are interesting:
Take ye enough spirits of hartshorn, rectified with human bones, but be sure the bones are well dried and broken into smithereens. Add two pound's of viper's flesh. Distill this mixture into spirit, oil, and volatile salt. Set it in earth for three months, and you will find that the oil separates off. Keep the oil. Use 20 to 60 drops, mixed into a glass of canary, for faintings, for apoplexies, for sudden and alarming onsets and for lethargies.
As for the spirits of hartshorn, be aware that it is best made from shaving the antlers of the red deer, destructively distilling the shavings until they develop into a solution of ammonia in water. My sources tend to scoff at an attempt to shave the horn of a unicorn. As for the human flesh, my sources are silent, though I imagine that the flesh of a murderer stung to death by vipers might suffice.

Seasickness
Tim Elliot
The general experience among members of the Cruising Association (survey last year or the year before) is as follows:
1. You can't cure it - once you're seasick, very few recover before next harbour (unless you're off to the FSOW).
2. There are several different preventions: medicines (Stugeron, Kwells, SeaLegs etc), motion-sickness wrist bands, etc. All must be begun before departure. There is no remedy that works guaranteed for everybody, so you try them out till you find the one that works for you. Stugeron is the one that works for the highest proportion. The wrist-bands do work for some people.
3. Keep your eyes looking outside the boat, preferably at the horizon.
4. Having an absorbing job to do helps, for instance steering; provided you don't have to use the compass constantly. Don't read while below; take it into the cockpit.
5. CA members experience is that avoiding certain foods doesn't consistently make a difference; definitely avoid booze; and when it's all over, if you've been sick, a banana is the absolute fastest pick-me-up.
6. If at all possible, make the first day an easy one (start early while not tired, avoid starting with a night passage, avoid lumpy seas).

Gretchen Mini
As one who has vast experience of being sick a-sea, I highly recommend scopolamine patches. Ginger? Wrist bands? Dramamine? Bonine? Fuggadaboudit. Go directly to the hard drugs. They aren't without side-effects, some unpleasant, but really it's all about choosing the lesser of two weevils.

Martin Watts
My mother was prescribed Stugeron for non-nautical medical purposes.
She always referred to it as "Stagger on".