Google search turned up this:
Keep this kit handy and update it every so often to ensure that the liquid's and pill's freshness are still intact, and that any used items have been properly replenished.
Storage container with tight-fitting lid
Muzzle (rope or strip of cloth)
Can't overestimate the importance of this. A dog WILL bite if it hurts enough.
Modern digital oral thermometers are fine. Normal dog temperature is reported to be 100-102.5 F, cats up to 103 F
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Panalog (antibacterial eye ointment)
Medicated ointments can sometimes make things worse. Also, panalog is a brand-name ointment that isn't for the eyes. A bottle of saline eye rinse (same as people use) would be better. As a topical wound treatment, plain old neosporin is a better choice.
Furacin ointment
Syptic Powder
Pepto-Bismol
Milk of Magnesia
I'm not a big fan of any of these. Furacin might be useful if it was all you had for a few days, but there are better choices such as plain old neosporin. Styptic powder will stop bleeding from over-agressive nail trimming, but isn't good for much else (and digging the nail into a bar of soap generally works as well). Pepto-bismol will turn the stool dark and so may mask blood in the feces; and both pepto and kaopectate contain an aspirin-like compound (NOT for use in cats!).
Dramamine
Baby aspirin (buffered or enteric, not ibuprofen)
Kaopectate
Hydrogen Peroxide
Peroxide is good to induce vomiting, but will slow wound healing if it's used as a disinfectant. Betadine works better as a disinfectant and is less irritating to tissues.
KY is often a better choice. It is available in small, sterile packets and is more compatible with body tissues.
Povidone/iodine is kinder to tissues than alcohol and an excellent disinfectant. Using alcohol to cool a heat-stroke dog can cause big problems. So I'd substitute the povidone/iodine for alcohol.
This can be used instead of drammamine as well. It's not quite as effective, but can save space in your first-aid kit.
Cheracol - D Cough Syrup
Mineral Oil
Mylanta
These are generally not that useful for dogs. I'd leave them out.
Doses by Weight of Dog
Buffered or enteric aspirin: 1 five-grain tablet per 30 lbs every six hours
5 grains is an adult tablet, I think (325 mg). Doses I've seen published for aspirin are usually lower (about half of a 325 mg tablet in a 30 lb dog), and longer (12 hours rather than 6). Keep in mind that studies have shown aspirin is much more likely to cause stomach ulcers in dogs than in humans. NO ASPIRIN OR ACETOMINOPHEN IN CATS! NO IBUPROPHEN IN DOGS OR CATS! (I'm sure most of you already know that, but I feel compelled to say it anyway...)