This is a relatively old article. There are other pharmaceuticals used to investigate whether they reduce stuttering frequency and / or severity. However, it should be noted that there have been no clinical trials that confirmed that any drug reduces stuttering frequency of severity. There are clinical case studies of specific drugs, but those are never enough to confirm that there is a benefit. Drugs to reduce anxiety will reduce anxiety. This can reduce the exacerbation anxiety has on stuttering. But there are no confirmed drugs that specifically reduce stuttering.