Dear Mr. Rawles,
I am a physician in Iowa and have read SurvivalBlog and many books related to survival including yours. In general there are many good thoughts and insights in the Blog. History predicts the future and some facts of history seem to have been overlooked by many survivalists. Many predict that in a long term situation, those left would be in an 1880s situation.
In Iowa, most counties had a peak population in the 1880 census. Most counties in Iowa have lost population every census since then (1940 was generally flat) this means that the land could support more people if individuals and society were prepared. Furthermore, if society were to collapse there would be trillions of calories of food in dent corn, soybeans and livestock which farmers would gladly exchange for anything useful. This would help bridge the gap in food production. This situation is common throughout the midwest. I would argue that west of the Mississippi is just as good as west of the Missouri River. Iowa does not have any very large cities and there are limited bridges over the Mississippi. Note what happened over the Mississippi River Bridge after Katrina where local law enforcement prevented refugees from crossing the river.
Many point out that in the north, if TEOTWAWKI were to happen in the winter, most would freeze, not starve. This is probably fairly certain outcome. Economic panics seem to develop in the Fall, meaning the winter would be a fairly likely time for an economic collapse to occur. Preparing to heat your house or remote location without power is fairly easy. This would limit the Golden Horde as many would freeze in place and limit the distance traveled of those that do leave. This would lower the effective population density of the north.
A study of the history of medicine came to a conclusion that it was not until the 1930s in which a person was probably helped more than harmed by seeing a physician. Antibiotics were the main reason for this. Other studies indicate that plumbers have saved more people than physicians by improving sanitation. I am not certain about the second statement but the point is valid. Sanitation needs to be a prime concern, mostly with respect to clean water. Prevention of a disease is better than treating it. Infections could be treated fairly well with a few antibiotics which have a long shelf life. Most human to human only infections are viruses and since nearly everyone is now vaccinated to most of these, and travel would be limited, these should not be a big problem for many years post TEOTWAWKI. Most bacteria are not specific to humans and antibiotics would be worth their weight in gold. Although any antibiotic would be valuable post TEOTWAWKI, Doxycycline should be included in any pharmacy. It would be effective against tick borne infections as well as Brucellosis from infected meat and milk, chlamydia and malaria. Some of these are bacteria that are inside the host cells and other antibiotics would not be helpful and the bodies immune system is not good at fighting them. I relearned this by an infection that I received while backpacking for three days. I am normally very careful to check for ticks every evening after being outside. But while backpacking, this was not done as I was tired and did not remove all my clothing. After returning to civilization I noticed a lesion that ultimately turned out after becoming very ill to be Tularemia (this was in Wyoming). There are several more common similar diseases Lyme Disease and Rocky Mountain Spotted fever being the most common. As people would be outside more and personal hygiene would suffer these infections would be common. These infections become chronic or fatal. Most other infections would be fought successfully by your immune system, an appropriate antibiotic would be helpful but often not needed. I do not have great advice as to how stockpile antibiotics. Physicians would probably be more comfortable giving these as prescriptions than narcotic pain killers. I do not know anything about veterinary medications. Although narcotics may be nice and valuable post TEOTWAWKI, they are unlikely to be life saving.
One pain killer that would be very life saving post TEOTWAWKI and has a long shelf life is aspirin. This should be the first stocked drug. If you have a heart attack and you take an aspirin you cut the risk of dying in half. Do not take it if bleeding is an issue so after in injury it may not be a good option.
If you really think that narcotics are important, remember that opium, the mother of all narcotics was and still is made from poppies grown in temperate climates. I do not know what is legal but you can by poppy seeds to eat or plant. In case you do not take my advice and buy aspirin when it is cheap and legal, you can try making it from willow bark.
The first medical book someone should get is the Merck Manual
The other area of medicine that made a big difference in life expectancy is obstetrics. Until the early 20th century, men outlived men because of child birth. Until recently the advise to women was to not gain more than 26 pounds. This was based a on pre-C section study from Germany which would be very important post-TEOTWAWKI. Folic Acid and iron supplements are important in early and late pregnancy. Iron supplements should last forever. In the Middle Ages, a iron nail was placed in an apple for a day before a pregnant woman was to eat it. Folic acid has an unknown shelf life but of course is provided by vegetables.
If a women has previously had a C-section and needs to deliver in a less than modern health system, a vaginal delivery [VBAC] would almost certainly be better that doing a repeat C-section in a less than ideal situation. There are no good easy options as to how to deal with a failure to deliver naturally post TEOTWAWKI. If you have figured out clean water, food, heat, security and sanitation, study obstetrics. The first vitamin deficiency noted by sailors on a diet without fresh food was scurvy, from Vitamin C deficiency. Vitamin C is found mostly in fruits and some vegetables. Apples have been the traditional source of Vitamin C in Europe and North America in the winter because of their long shelf life. Pure Ascorbic Acid, Vitamin C, has an shelf life of many decades. GNC and other nutrition stores sell this.
Salt was extremely valuable before the modern era. In some areas gold and salt were of equal weight value. Ancient salt mines in Europe have evidence of many thousands of years of use and traded goods from many hundreds of miles away. You can grow everything your body needs, but not salt. It is cheap now and if you keep it dry never spoils. Get table salt with iodine to prevent goiters if you live in an area with low iodine concentrations. The Non radioactive iodine in it may also be important if radioactive iodine finds its way to your location. Salt blocks for livestock may be an okay long term option for livestock and humans. Salt for water conditioners does not have iodine but would be useful most of the time.
Another historical fact that seems to have slipped past preppers is that Thomas Edison developed the iron-nickel battery for electric vehicles. Some of these have been running 100 years. I have ordered one but do not yet have experience with them. It seems that with solar panels and a iron-nickel battery system your children will always have power. These do not freeze, making them especially good for remote northern locations.