Medical kit advice

For gastrointestinal problems:
Loperamide (trade name Imodium): Useful for diarrhoea, although the most important thing to do is keep yourself hydrated. It is useful to relieve pain if nothing else. Take two tablets with the first loose stool and then one for every subsequent one.
Dioralyte: Or other rehydrating mixture, especially if diarrhoea is severe.
Antibiotics: If you note blood with the stool or develop a temperature, a short course of ciprofloxacin should do the trick. If diarrhoea continues (especially if it may be amoebic or giardiasis infection) with nausea, frothy stools and lots of wind metronidazole would be a wise choice.
Cyclizine or prochlorperazine: May help if nausea and sickness is a major problem.
Oral rehydration therapy (ORT): Put one 5ml teaspoon of salt with eight teaspoons of sugar in one litre of CLEAN drinking water and take 1–2 cups with each loose motion.

For allergies/insects:
Chlorpheniramine: (For example, Piriton) or promethazine is handy for most allergies, including those to insect bites. It also helps in motion sickness. It can make you drowsy, but this can also be an advantage if the itchiness is keeping you awake.
Insect repellent: (And often a net) are essential. See malaria. If you’re really prone to being bitten, ‘after-bite’ type remedies are available.

For throat/skin infections:
Augmentin (Or doxycycline) is handy for a bad sore throat, most chest infections and skin that has become infected secondary to bites or sores. Combinations of amoxycillin with flucloxacillin can also be used.

For trauma/pain:
Analgesic: (aspirin or paracetamol or codeine/paracetamol combination). Note the latter can make you drowsy and bung you up … handy when you’ve finished the loperamide.
Bandages and plasters: Handy for blisters.
Syringes and cannulae: These are for the adventurer who is going places you really don’t want to be getting ill. Areas with high HIV and hepatitis levels are not areas to have accidents. Although taking your own cannulae may protect you from contaminated needles, it won’t help you much if it is being used to give you infected blood. If you really are going to take such risks, a bag of gelofusin or similar may be a good idea (although the chances are if you need it, you’re not going to be in a fit state to set it all up).

General things:
Sunscreen
Water purification tablets/iodine drops
Scissors ± tweezers
Antiseptic cream/Fucidin ointment