Slow lorises are threatened by deforestation and the wildlife trade, including the exotic pet trade, traditional medicine, and bushmeat. Because of these and other threats, such as habitat fragmentation, selective logging, and slash and burn agriculture, slow lorises (genus Nycticebus) are listed as either "Vulnerable" or "Endangered" by the International Union for Conservation of Nature (IUCN). Their conservation status was originally listed as "Least Concern" in 2000 because of the frequency in which these primates were found in animal markets and imprecise population surveys. Because of their rapidly declining populations and local extinctions, their status was updated and in 2007 CITES elevated them to Appendix I, which prohibits international commercial trade. Local laws also protect slow lorises from hunting and trade, but enforcement is lacking in most areas.
Slow lorises have been a part of the traditional beliefs of Southeast Asia for at least several hundred years. Their remains are buried under houses and roads to bring good luck, and every part of their body is used in traditional medicine to make everything from love potions to unproven cures for cancer, leprosy, epilepsy, and sexually transmitted diseases. Furthermore, a large number of slow lorises are traded as pets, both locally and internationally. Although it is illegal to import slow lorises for commercial sale, they are popular pets in Japan, the United States, and Europe, largely due to their "cute" appearance, which has been popularized in highly viewed YouTube videos. Captive lorises experience improper care and die from poor nutrition, stress, or infection. Despite this, demand has risen, and slow lorises are no longer captured opportunistically, but are now hunted on a commercial scale using flashlights, from which the animals do not flee.
Connected protected areas are important for the conservation of slow lorises because these primates are not suited for traveling long distances on the ground. Training for enforcement officials helps improve identification and the awareness of their legal protection. Sanctuaries and rescue facilities are available to provide both temporary and lifelong care for confiscated slow lorises. Zoo populations of some species have not bred much recently and are growing too old to reproduce, although the pygmy slow loris is doing well at some facilities, such as the San Diego Zoo.