Extreme heat can cause formulas to melt and ingredients to separate. This causes products, especially those with active ingredients such as sunscreen, to become less effective. For this reason, always store skin care products at room temperature and out of direct sunlight.
Most of our brands have been rigorously tested to make sure they can withstand extreme temperatures. They are frozen, thawed, heated, brought back to room temperature and frozen again to make sure they can still be used and effective after travel. You would just need to let the product return to room temperature before use, and it will still work for you!