Drug Law is a subcategory of Criminal Law. Most if not all Criminal Lawyers are well-qualified to represent and assist individuals charged with relatively minor drug offences like possession. In some situations, although not necessarily with the same success in the case of repeat offenders, a Criminal Lawyer will often be able to negotiate a resolution of the matter that does not involve a criminal record.
If you find yourself under suspicion or charged with a more serious drug-related charge, a charge in other words related to trafficking or otherwise with respect to a large quantity of illegal drugs, you will most certainly want the assistance of a Drug Lawyer, that is, a Criminal Lawyer who specializes in defending drug offences. You may find that a Drug Lawyer is very creative in finding ways to negotiate a resolution that minimizes the disruption in your life.
The most important thing to keep in mind when caught up in a drug bust or otherwise involved in a drug trafficking case is to say nothing without first speaking to a lawyer. Beyond that, do not agree to sit down with investigators and answer questions without your Drug Lawyer present.