Its a good question, and you should probably talk to your doctor and pharmacist about it. A lot depends on what you are allergic to and where you are going. When you go cruising you really change your
environment, so you may leave some allergens behind (and pick up new ones, but it usually takes some time to sensitize yourself to new allergens).
For example, I managed to leave the acacia and pine pollen behind, but was really affected by the grasses which grow on Easter Island.
If you are allergic to your spouse, you may not get relief....