To be honest I don't think Kava has any recreational value at all. I used to take it for sleep, but I found the effects to be a little nauseating. Is it safe to mix it? Generally it's recommended to not mix it with other CNS depressents but it depends on your dosage. If you take a dose of methadone that is borderline OD territory, then the Kava my put you over the edge. If you are taking it in tea form it's really difficult to quantify the ingestion amount.
It's also been found in some instances to be hepatotoxic, though this may depend on what part of the plant is used for the supplement, as well as the consumer's own body.
You could also try mixing alcohol or a benzo with the methadone. This is NOT RECOMMENDED, but it's pleasurable. With a relatively low (safer) amount of methadone you could have for example 1 beer or 0.5mg of Xanax. I however never liked mixing drugs. I've found that enjoying a drugs individual effects works best for me. If I have alcohol however, judgement about taking multiple substances goes out the window. In other words, very dangerous combinations.
