Shaking while on drugs or shaking while sober after a period of drug use? Are you on any medications?
The medical advice for dealing with a drug- or medication-induced tremor is to discontinue the drug or medication. If it persists and it's bad enough for you to worry about, you should see a doctor to rule out serious medical causes.
There are medications for specific tremors (Parkinsonian tremors, non-Parkinsonian action tremors, etc) but the treatments are different depending on the type of tremor and they've all got pretty serious side effects. People are generally only prescribed them if the tremor is seriously debilitating (i.e. having a major negative impact on your life) or likely to get worse.