And for US airlines:
Appendix A to Part 121 of Title 14 of the Code of Federal Regulations (14 CFR 121) includes the specific requirements for US carriers:
For 0-50 seats, one kit is required, 51-150 two kits are required, 151-250 requires three, and more than 250 requries 4 kits.
That kit must include, at a minimum:
16 Adhesive bandage compresses, 1-inch
20 Antiseptic swabs
10 Ammonia inhalants
8 Bandage compresses, 4-inch
5 Triangular bandage compresses, 40-inch
1 Arm splint, noninflatable
1 Leg splint, noninflatable
4 Roller bandage, 4-inch
2 Adhesive tape, 1-inch standard roll
1 Bandage scissors
Also, at least one approved medical kit must be on board that includes, at a minimum:
1 Sphygmonanometer
1 Stethoscope
3 Airways, oropharyngeal (3 sizes): 1 pediatric, 1 small adult, 1 large adult or equivalent.
Self-inflating manual resuscitation device with 3 masks (1 pediatric, 1 small adult, 1 large adult or equivalent).
CPR mask (3 sizes), 1 pediatric, 1 small adult, 1 large adult, or equivalent.
1 IV Admin Set: Tubing w/ 2 Y connectors
2 Alcohol sponges
1 Adhesive tape, 1-inch standard roll adhesive.
1 pair Tape scissors
1 Tourniquet
1 Saline solution, 500 cc
1 pair Protective nonpermeable gloves or equivalent
6 Needles (2-18 ga., 2-20 ga., 2-22 ga., or sizes necessary to administer required medications).
4 Syringes (1-5 cc, 2-10 cc, or sizes necessary to administer required medications).
4 Analgesic, non-narcotic, tablets, 325 mg
4 Antihistamine tablets, 25 mg
2 Antihistamine injectable, 50 mg, (single dose ampule or equivalent).
2 Atropine, 0.5 mg, 5 cc (single dose ampule or equivalent).
4 Aspirin tablets, 325 mg
1 Bronchodilator, inhaled (metered dose inhaler or equivalent).
1 Dextrose, 50%/50 cc injectable, (single dose ampule or equivalent).
2 Epinephrine 1:1000, 1 cc, injectable, (single dose ampule or equivalent).
2 Epinephrine 1:10,000, 2 cc, injectable, (single dose ampule or equivalent).
2 Lidocaine, 5 cc, 20 mg/ml, injectable (single dose ampule or equivalent).
10 Nitroglycerin tablets, 0.4 mg
1 Basic instructions for use of the drugs in the kit.
Also, "At least one approved automated external defibrillator, legally marketed in the United States in accordance with Food and Drug Administration requirements" must be stored in the passenger cabin.