MyAdvocate has comprehensive distribution options however the drug test condition is something that is problematic and can be interpreted in many ways. What is illegal today might be legal 5 years from now. There are two ways to incorporate various testing conditions;
1) Use Trustee Discretion or In Trust for Lifetime which will give FULL power to your trusted person (Trustee) or group of people you select to determine if the beneficiary has met the spirit of your intentions and release portions or all the assets.
2) Continue to use the various distributions options you may have chosen, HOWEVER, any Health, Education, Maintenance, and Support (HEMS) distributions before those distributions are required to be made at the discretion of your trustee and in the spirit of your intentions such as a drug test.
Here is an article on HEMS