Medicinal cannabis produced overseas will be easier to access for terminally ill patients, after the Senate voted to remove tighter controls imposed by the Federal Government.

The changes will restore 'fast-tracked' access to some unregistered medicinal cannabis medications produced overseas, but the move has been slammed by the Government as "reckless".

While taking steps last year to make medicinal cannabis more accessible, the Government also put in place stricter regulations.

While doctors previously only had to notify the Therapeutic Goods Administration (TGA) of their intention to treat a terminally ill patient with the unregistered medication, the changes forced doctors to apply to the TGA for permission.

The changes moved the medications from what is known as category A of the special access scheme to category B.

Advocates for medicinal cannabis argued it slowed down access for terminally ill patients.

Under questioning in Senate estimates recently, TGA officials said category B applications were being decided on generally within 48 hours, and all had been approved.

The Senate has now voted to reverse that change, despite the opposition of the Federal Government.

Greens leader Richard di Natale moved the disallowance motion in the Senate, and said it reopened a pathway that should be available to the terminally ill.

"If you have a terminal illness, then you should be able to get access to treatment that is going to improve you quality of life," he said.

The decision was supported by Labor, One Nation and other crossbenchers.

Government says decision 'risks lives'

Health Minister Greg Hunt said there was already a safe and legal way to access medicinal cannabis, and this decision simply removed safeguards.

"They have acted in defiance of the advice of the TGA, in defiance of the advice of the leading medical practitioners in the AMA and the College of GPs, even in defiance of the views of Palliative Care Australia," he said.

He said it was a dangerous decision, and that he was seeking advice about the Government's options.

"The TGA could not be clearer, that it is a potential risk not just to health, but to lives," he said.

"It is unfortunately a reckless and irresponsible decision, I would call upon [those who voted for it] to reflect upon that.

"We cannot accept this, and I have asked the TGA for advice."