in no specific order
1-Tylenol/APAP This medication has many uses and specifically if we are talking austere I think of war time or where soft tissue injuries may be more common and infections, fever etc..
2-broad-spectrum antibiotic- I think this is self explanatory.
3-Ketamine-analgesic, sedation etc.. It's my version of a benzon had a baby with a narcotic! lol..
4-Benadryl-great all around medication. many uses, nausea, allergies etc.
5- Fentanyl- I view austere as well the end of the world situations and maybe you need to allow someone to go peacefully into the night. Sedate with Ketamine and push a large bolus of Fentanyl and let them go.
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6- NS- again self explanatory. I'm leaving this off my top 5 because