can people get addicted to it?
Yes, they are often associated with addiction or drug dependence.
Psychoactive drug
Psychoactive drugs are often associated with addiction or drug dependence. 
what takes over the function of photosynthesis in opuntia In the absence of leaves, enlarged stems carry out photosynthesis. what is a cactus? It is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. how did they evolve? Except for a relatively recent spread of "Rhipsalis baccifera" to parts of the Old World, cacti are plants of South America and mainly southern regions of North America. This suggests the family must have evolved after the ancient continent of Gondwana split into South America and Africa, which occurred during the Early Cretaceous. how do they reproduce? Cactus flowers are pollinated by insects, birds and bats. how are they classified? Botanists, such as Philip Miller in 1754, divided cacti into several genera, which, in 1789, Antoine Laurent de Jussieu placed in his newly created family Cactaceae. who is the former person mentioned? An English botanist of Scottish descent. and the latter? A French botanist. what was his heritage? The system of suprageneric nomenclature in botany is officially dated to 4 Aug 1789 with the publication of the Genera Plantarum (Gen. Pl.). where was he from? Paris what was his contribution to his field? He is notable as the first to publish a natural classification of flowering plants; much of his system remains in use today. what does the aforementioned plant feed on? UNANSWERABLE what are its uses? They are used for human food and as fodder for animals, usually after burning off their spines. In addition to their use as psychoactive agents, some cacti are employed in herbal medicine. what is the agent just mentioned above? A psychoactive drug, psychopharmaceutical, or psychotropic drug is a chemical substance that changes nervous system function. is it used as an anesthetic? General anesthetics are a class of psychoactive drug used on people to block physical pain and other sensations.
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Psychoactive drug [SEP] Addiction and dependence
Psychoactive drugs are often associated with addiction or drug dependence. Dependence can be divided into two types: psychological dependence, by which a user experiences negative psychological or emotional withdrawal symptoms (e.g., depression) and physical dependence, by which a user must use a drug to avoid physically uncomfortable or even medically harmful physical withdrawal symptoms. Drugs that are both rewarding and reinforcing are addictive; these properties of a drug are mediated through activation of the mesolimbic dopamine pathway, particularly the nucleus accumbens. Not all addictive drugs are associated with physical dependence, e.g., amphetamine, and not all drugs that produce physical dependence are addictive drugs, e.g., caffeine.