Glasses and Contact Lenses
If you wear glasses or contact lenses, take along an extra pair and bring a copy of your prescription. Contact lenses can be expensive to replace overseas. You might consider bringing a supply of wetting and cleaning solutions, just in case your favorite brand may not be available overseas. It may be possible to use another brand of solution instead; check with your ophthalmologist.
If you use an electrical disinfecting unit for soft contacts, you may want to switch to chemicals, since even with a converter the unit may not function well on electrical current in other countries.
Never pack your lenses in checked luggage! If a suitcase goes astray, you don't want your lenses to be lost as well! Always pack lenses and any type of medication in carry-on luggage.