More judges will be needed now that methamphetamine, or P, cases can be heard in district courts instead of the High Court, says lawyer Marie Dyhrberg.
Ms Dyhrberg says it already takes up to a year to obtain a date for a trial in Auckland.
In May, 245 cases were waiting to be heard in the High Court - almost half of them methamphetamine related.
All class A drug cases will still go before the High Court, but those considered less complex can then be passed to district courts.
Courts Minister Rick Barker says it will not mean they are treated any less seriously because they are class A drug offences. Sentencing options have not changed.
However, Ms Dyhrberg says it already takes up to a year to be granted a date for a trial in district courts in Auckland.
She says that irrespective of where such drug cases are heard, the courts still have to deal with the backlog and they will need more resources to do this.
Chief District Court Judge Russell Johnson says the changes will be monitored closely and he will not waste time in asking for more resources if they are needed.
Meanwhile, pharmacies are adding their support to a call for the introduction of a nationwide tracking system to help tackle methamphetamine production.
Police say the system, which links pharmacies, has been trialled in Queensland and has been successful in cutting down production of the drug.
They have made submissions to the Government to introducing a similar scheme. Pharmacy Guild chief executive Annabel Young believes such a system would be effective.