They can produce secretions but the toxicity of those secretions is correlated with their diet. This applies to both reptiles and amphibians broadly.
Here's a salient snippit from an excellent science source that I highly recommend for those seeking scientific references for such topics:

"The source of many chemicals that occur in amphibian skin appears to be the arthropods in their diets, particularly ants. Clades within the Bufonidae (e.g., Rhinella), Microhylidae (e.g., Microhylinae), Mantellidae (e.g., Mantella), and Dendrobatidae (e.g., Dendrobates, Adelphobates, Ranitomeya, Oophaga, and Phyllobates, for example) specialize on ants and produce some of the most toxic skin compounds. The suggestion that some frogs may optimize chemical intake for defense when selecting prey is supported by comparisons of the diets of frogs and lizards from the same microhabitats. Many leaf litter frogs of Amazonian forests feed on ants, even though more energetically profitable prey are available based on diets of lizards in the same microhabitat. The ant-eating frogs produce noxious chemicals in the skin, whereas those that eat few ants do not produce toxic skin chemicals (Fig. 11.19). The correlation between ant eating (myrmecophagy) and skin toxins is best supported for dendrobatid frogs. Ant eating, production of noxious or toxic chemicals in the skin, and aposematic coloration have evolved independently several times. Based on their presumed phylogenetic relationships, these traits have evolved together (see Fig. 10.29). A number of behavioral and life history traits have evolved concordant with myrmecophagy, including increased activity, reduced clutch size, and more extended parental care, including either prolonged feeding of tadpoles or long-term pair bonds in some lineages. The possibility exists that release from predation by visually oriented predators has relaxed some of the constraints imposed by low levels of activity in cryptic species such as Allobates, resulting in the evolution of complex social behaviorsinvolving high levels of activity in other genera, such as Dendrobates, Oophaga, and Ranitomeya. Species of Allobates eat few ants, are not aposematically colored (with one possible exception), do not produce skin toxins, and rely on crypsis for escape from detection by predators."

https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/anaxyrus