Having a small first aid kit is important for any angler. We sling pointy things from a long pole to catch wiggly things with pointy things on their back and in their mouth. Every fisherman will eventually shed a little blood for the sport.
A first aid kit is even more important for a kayak fisherman. Unlike boaters or shore fishermen, kayakers depend on their body, most notably their hands and arms, to get home. When A kayaker cuts his hand he can't just pack up and go home, he has to paddle for an hour with his injury to get home! Also, kayakers are closer to the danger than other fishermen. This adds to the excitement, but also requires some common sense safety.
In my dry box I keep another, smaller dry box with some first aid essentials. It is easy to go overboard, but I try to strike a balance between bulk and function.
The first aid box I use is a Plano 3430 . It only costs $5 and is very watertight.
On top I keep a standard collection of band aids and alcohol wipes. The disinfectant wipes are important. When you are down at water level you get splashed and slimed by fish. This is just asking for an infection.
Under that I have some more serious bandages, butterfly stitches, some pain meds, and some cold tablets. The pain and cold tablets are for when I am feeling good enough to fish, but bad enough not to enjoy it.
The next layer has a nice, large strip of moleskin, and a match box filled with antacid. Moleskin is a savior when a blister starts to form.
Finally, at the bottom, I keep some tweezers, a roll of electric tape, some storm proof matches, a block of Trioxane, and a $5 bill.
The electric tape is for applying large bandages, waterproofing band-aids, and general repairs. The Firestarting supplies are for if I get stranded somewhere, a real possibility in some of the places I go. The $5 bill is just emergency cash. Sometimes there is a launch fee I don't know about or a bait shack that only takes cash. I never use cash, so this keeps me fishing.
The most important piece of first aid equipment I carry does not fit in this little box. It is a roll of Athletic Tape . It can support a sprained wrist or elbow, be used to keep a bandage on, or even be tuned into a make shift tourniquet. It is great stuff!