Depending on the conditions you encounter on a multi-day hike, medication storage can require quite a bit of forethought. A medication’s potency can be affected by temperature, sunlight, moisture, and humidity. So, what exactly is the best way to pack your meds to protect them from the elements for days, or even weeks, on end?

　　We’ve chatted with three pharmacists—who are outdoor enthusiasts—to give you their most helpful tips. They also offer advice on ensuring you can properly store the medications so that you can traverse the wilderness with peace of mind. Here’s what they had to say.

　　Schedule a “Vacation Override” with Your Doctor to Get More Doses in Advance If your current batch of medication refills is going to run out while you are in the middle of your trip, and you anticipate that it will be difficult to get a pharmacy refill in the area you’ll be in, organize a vacation override beforehand.

　　A vacation override allows you to get earlier fills of your prescription, so you have what you need on your trip. Speak with your doctor and pharmacist about your plans to fill your prescription early, says Adam James, a pharmacist and manager of immunization and clinical programs at Rite Aid. They will work with you to request the vacation override from your insurance provider. Your insurance coverage for the refill differs depending on the plan you are on.

　　Of course, if you’re only going to be away for a couple of days and you happen to have a surplus of medications handy, go ahead and pack those extra doses. Stashing away some extra medication will also save you if you have to extend your trip, says James. Plus, if you happen to drop a pill in a river or between rocks, you’ll be covered.

　　Ask Your Pharmacist to Fill Your Prescription at a Pharmacy Near Your Destination An alternative to a vacation override is “having your pharmacy transfer your prescription and history information to a local pharmacy in the area close to where you plan to be, says Kimberly Terry, a clinical pharmacy manager at the University of Utah Health. It can be an independent pharmacy or pharmacy chain.” If you know that you’re headed to a relative’s or friend’s house, you can also mail the medication there, provided you use a tracked mail service, and the person receiving it knows how to store the medication properly, says James.

　　Just keep in mind, you cannot ship medication internationally, says Preston Eshenko, a clinical pharmacist at Gourlay’s Pharmacy in Alberta, Canada.

　　It’s a good idea to have a copy of your recent prescriptions from your physician, up-to-date lab results, and medical history with you when you’re on a multi-day hike, says Eshenko. It can be printed or stored on an electronic device like a phone. Not only does it aid the process of getting a refill at a pharmacy that is unknown to you, but it also helps in the event that “an emergency responder would need to give you some kind of medical attention or rescue you in an emergency situation,” says James. “Emergency responders are trained to look for that type of information, whether it be in your backpack or on your electronic device,” he says.

　　4 Ways to Store Medications Safely in Your Backpack Here are four pharmacist-approved ways to pack your medications safely before your next hike.

　　1. Protect Pills and Tablets From Moisture and Sunlight Exposing your medication to moisture (like humid conditions) can cause a decrease in your medication potency or, in some cases, make it toxic, says James. The same goes for ultraviolet light rays from the sun.

　　To protect your medication, if it comes in its manufacturer’s bottle, simply keep it stored in there, James shares. But if its been dispensed into plastic prescription vials, transfer the medication to a pill box that is specially designed for outdoor activities, he says.

　　Look for pill boxes that are waterproof, airtight, made of metal or anodized aluminum, and do not simply snap shut but have the added security of a locking clip—like this one. Unlike plastic prescription vials or generic plastic pillboxes, these specialty pillboxes are unlikely to crack or pop open and spill their contents out.

　　If you’re going to be in a humid environment, Eshenko suggests asking the pharmacist if the medication is originally packed with desiccants, packets of silica gel that absorb moisture, in its stock bottle. If it is, request for desiccants to be included in your repackaged medication.

　　Terry also suggests placing your medication bottles or pill boxes inside a neoprene medication bag or pouch. “If you drop it accidentally in a lake, it floats so you can easily retrieve it,” she says. Neoprene fabric is also waterproof, so you won’t need to worry about your meds getting soaked. As a bonus tip: it’s still probably a good idea to toss your pills in a plastic storage bag to be extra safe.

　　2. Account for Temperature Temperature is another thing that can damage your medications. When a medication label directs you to store it at room temperature, James says the ideal storage temperature range is 68 to 77 degrees Fahrenheit, though it can generally be stored between 59 and 84 degrees Fahrenheit.

　　To shield your medication from heat, always store it deep in the center of your pack, says Terry. In very cold climates, where temperatures plummet below freezing at nightfall, Terry advises keeping your medication in the inside pocket of your jacket. This helps prevent the medication from freezing while also keeping it from being exposed to direct body heat.

　　If you have a medication that must be refrigerated at 36 to 46 degrees Fahrenheit, the first thing to do is to ask your pharmacist if there’s any leeway to this rule. “Some medications that are normally kept cold can be kept out at room temperature, whether it be for a few hours, a few days, or even up to a month. It’s important for people to ask their pharmacist so that theyre able to get that information and plan accordingly for their hikes,” says James.

　　Should the pharmacist advise keeping your medication or injections cold while hiking, you could try this trick that Terry has seen work. Create an ice well in an insulated water bottle to store the medication by freezing water around a cylinder-shaped object and removing it to leave a hole. Alternatively, use an insulated cooler bag with ice blocks or packs.

　　3. Protect Brittle Medications Something else to keep in mind when hiking is that your tablets are likely to be bouncing around in their containers. They could break into pieces or disintegrate into powder, especially if they’re the fragile kind, Terry says.

　　When the time comes for you to take a dose, there’s a chance that you won’t be consuming the full, accurate dosage if you’re ingesting pill fragments or pills with broken surfaces. Because of this, she suggests packing your medications within gauze pads in the bottles or pill boxes. She prefers gauze pads over cotton balls because you can always repurpose them to treat a cut or graze.

　　4. Use a Pill Box to Prevent Medication Mix-Ups According to Terry, it’s important to “have the description of the tablet or the capsule, of what it looks like, what the medication is, and how youre supposed to take it, and have that affixed to either the top or the inside cover of the pillbox.”

　　This way, you can differentiate between your pills and easily remember what your dosing schedule is.

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