Did you realize some popular prescription and over-the-counter drugs are illegal in some countries? Things like pain relief, better sleep, allergies and even the common cold medicines.

The United Arab Emirates and Japan, for example, are among the most restrictive nations. However, other countries ban or restrict importing narcotics, sedatives, amphetamines, and others.

Most travelers won’t run into problems for carrying small amounts for personal use, said Katherine L. Harmon, who oversees health analysis for iJET International , a travel risk management company. But noncompliance can result in confiscation, (which could, in turn, have severe medical consequences), deportation, jail time, and even the death penalty. “Does it happen a lot? No. Could it? Yes,” Ms. Harmon said. “Consumers need to understand this and how it might adversely impact them before they book that awesome trip to an exotic location.”

Plan Ahead

Laws vary by country and there is no central, up-to date repository, so Ms. Harmon suggests consulting your physician, travel medical insurance company, or local pharmacist four to six weeks before traveling. “When you inquire about your shots, ask about medications. Odds are they may not know off the top of their head, but they have the resources to find out.”

She also suggests checking with the embassy of your destination country. The State Department  website lists foreign embassies in the United States, and their contact information. It also lists insurance providers  that offer overseas health coverage. Comparison websites Insure My Trip  and SquareMouth  can help assess those insurance plans, if they’re necessary.

Label and Pack Your Medication Properly

So, what should you do?

Remember to carry all of your medication, including vitamins and supplements, in their original, clearly marked containers or packaging. Put these in a clear plastic bag in your carry-on luggage. Make sure everything including the name on the prescription, the medicine container, and your passport all match. If you lost the product information insert, ask the pharmacist to print a new one for you.

Also, check the Transportation Security Administration’s website for up-to-date rules and regulations on packing and carrying your medication when you depart. The standard rules for liquid carry-ons don’t apply to medications in liquid or gel form, but you need to inform the T.S.A. when you pass through security so they don’t confiscate it.