When traveling with a chronic illness, securing a travel insurance policy with a pre-existing condition waiver is crucial, typically requiring purchase within 14 to 21 days of the first trip payment. Understand the insurer's look-back period and ensure medical evacuation coverage, which can be very costly. Regular health insurance often doesn't cover international care. Always fully disclose medical history to avoid claim denial and verify if ongoing treatments abroad are covered. Contact your insurer promptly if medical issues arise during travel.