Climbers beware of altitude sickness when scaling Mt. Kinabalu. Leeches are also commonly found in the rain forest, and leech socks are recommended for all climbers. Mosquito repellent that contains DEET can be difficult to find and is good to pack for any treks into the jungle. Various types of sunscreen are available; however, the better-known brands typically cost more. Traveler's diarrhea is common—you can help prevent it by avoiding tap water.