Just a few comments on this subject. All drugs, and medical products such as band-aids and iodine pads are sensitive to heat and humidity. That said there are some common sense things that can be done to keep some drugs with you. This first point has been touched on in other threads and posts. Don't ever leave any drugs in a car, airplane or anyplace where the temperature will climb very high (use common sense 1 hour Ok, 1 week bad). The high temperature will affect the effectiveness of the drugs to the point where they are not effective when you need to use the drug or medical product. If you carry drugs in a hot environment SoCal or any high temp and / or high humidity area you should realize that they will lose effectiveness in a matter of months not years. How quickly and to what degree depends on many factors including what the drug is, how it is packaged, and how you store it in your first aid kit. Some drugs will lose effectiveness to the point of being useless in a short time (months to even hours) at high temps and or high humidity (extreme examples would be some antibiotics, and Epi-pens for bee stings). A word on expiration dates of drugs - this is determined as the date where a percentage of the drug is found to still be effective for it's labeled use. This means that if you stored the drug under optimal conditions that x percent of the dosages of the drug would be effective at the expiration date. The percent is determined by the Food and Drug Administration and the drug industry and is most often very high (95% or above in many cases). What this means for the average consumer is that if an over the counter drug expired last month and has been stored in your house it will still be effective now but in a short time may not be effective. But (there is always a but in advice) if you exposed the drug to high temp or high humidity the drug has a high probability of not being effective. Now some very general things you can do:<br><br>If possible, leave drug in original packaging. Don't leave drugs for long periods of time in high heat or humidity. Exchange or use drugs before they expire. <br><br>If as in the case presented here: carrying a first aid kit in hot weather make sure that the drugs carried have an expiration date as far in future as you can find. Then at the end of the hot season remove those drugs exposed to heat, put these in your medicine cabinet for short-term use, and refresh FAK with new drugs. Don't just do this with drugs but if possible with band aids and all other medical products.<br><br>Some generalizations: Tablets are more stable than gelatin capsules, over the counter are more stable than prescription, and the less complex the drug the more stable. Ask your pharmacist for help if you are unsure about a drug you need or want to carry. <br><br>Expiration dates are a matter of playing the percentage. If you are going camping this weekend, but your drug expired in May, and it is tough to get more this week then play the percentage. Now most of the people on this forum are cautious so I would say exchange your drugs after some sort of stress like the summer months in SoCal, but always try to exchange at or before expiration date.<br><br>Two other things: 1 - I feel that consulting your doctor about any concerns storing or using drugs is part of being prepared for anything involving your health - this includes what to put into a FAK and how you should pack a FAK. 2 - FYI for the group. My background is the pharmaceutical industry - quality control and research - 15 years and counting in the industry with large and small firms.<br><br>One last thing related to another thread-carrying drugs in a PSK. Drugs needed for your survival should be included (IMHO) because the purpose of a PSK is survival and if you die because your heart medication is somewhere else then the point of carrying a PSK is moot. A personal note on this -- I carry a Epi-Pen because of bee sting allergies (yes to the point of being lethal if I don't get a shot). Fitting a Epi-Pen in an Altoids tin is very hard ; ) but I still carry it everywhere from spring to late fall. <br><br>Just some ideas and opinions. Take care and stay safe<br><br>CJ in Wisconsin