Terri Eskdale never imagined becoming an advocate for voluntary euthanasia laws, but after watching her partner Mark Brennan's health deteriorate as he battled multiple sclerosis (MS), the issue was thrust upon her.

Mark had battled MS for decades and as the disease took hold of his body he decided to end his own life.

Without the option of voluntary assisted dying laws, his death was a lonely one and caused his family great pain.

"You never really know if someone is going to follow through with something like that so yes, it was a shock," Terri said.

"I tried to be brave and strong, but really I was very shocked, very sad really, sad that I couldn't be with him and that he had to die alone."

The experience led Terri to tell Mark's story to a 2015 parliamentary inquiry examining end of life choices.

Terri Eskdale with her partner Mark Brennan, who ended his life after battling multiple sclerosis for decades. ( Supplied: Terri Eskdale )

Her submission urged politicians to make sure people did not have to die without support.

"People should be able to choose a time to die and have people, loved ones around them and die free of trauma because people are killing themselves already. People are ending their lives in unusually cruel ways anyway," she said.

Informed by the inquiry, the Victorian Parliament passed the Voluntary Assisted Dying Act in November 2017.

After an 18-month implementation phase, the laws will become active on Wednesday.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 12 seconds 1 m 12 s The Victorian Government expects about a dozen people to use the laws in the first year

Premier Daniel Andrews said the Government had received about 100 inquiries from people seeking to use the new laws.

"We anticipate in the first 12 months, based on overseas experience, around a dozen people that will access voluntary assisted dying," he said.

He said that number was projected to stabilise at about 100 or 150 people per year.

How will it work? After all approvals, a kit is delivered to a person's home

After all approvals, a kit is delivered to a person's home A representative will take the person through the process

A representative will take the person through the process Other people can be present during this instruction

Other people can be present during this instruction The kit contains the patient's information and step-by-step instructions that may be translated

The kit contains the patient's information and step-by-step instructions that may be translated It also contains a locked box with the medication inside

It also contains a locked box with the medication inside A key to the box is provided to the patient

A key to the box is provided to the patient There are also some pre-medications to take prior to taking the substance

There are also some pre-medications to take prior to taking the substance The patient will mix the medications themselves before taking the fatal dose

Applicants must be Victorian residents, aged over 18 and be assessed by two doctors to have a terminal illness with intolerable pain that will likely cause death within six months or 12 months if the illness is a neurodegenerative condition like motor neurone disease.

The laws also have safeguards to prevent terminally ill people being pressured into a decision.

Anyone who is the beneficiary of the person's will cannot be among the two witnesses required to sign the application.

Authorities will not reveal the exact make-up of the drug prescribed under the Voluntary Assisted Dying Act.

But it is similar to the product Nembutal.

It will be dispensed by pharmacists at the Alfred Hospital, which was asked by the State Government to provide the service.

A lethal dose of the drug is combined with two other liquids immediately before consumption. ( ABC News: Danny Morgan )

The hospital's director of pharmacy, Michael Dooley, said the medication would be provided in a locked box and have instructions on how it should be taken.

"The role of the statewide pharmacy service is to go to the patient and provide the medications, to do that in a compassionate manner, to make sure the medications are provided in a way that's safest for them and to answer any questions," Professor Dooley said.

"It's really important that everyone understands that our role is to supply the medications and the education. The pharmacists' role is not to administer the medications.

"The medications are self-administered by the patient at a time and place of their choosing."

Patients will take a glass, mix the drug with two liquids provided by the pharmacist and swallow the mixture.

Eligibility criteria Victorian, over 18

Victorian, over 18 Has an incurable disease that causes "suffering to the person that cannot be relieved in a manner that the person considers tolerable" (Act p.15)

Has an incurable disease that causes "suffering to the person that cannot be relieved in a manner that the person considers tolerable" (Act p.15) Received a prognosis of less than six months or 12 months for neurodegenerative conditions, such as multiple sclerosis, motor neurone disease

Received a prognosis of less than six months or 12 months for neurodegenerative conditions, such as multiple sclerosis, motor neurone disease Has decision-making capacity

Has decision-making capacity Independently making the decision at the time of being unwell (patients cannot pre-plan voluntary assisted dying or request if suffering from dementia)

"Soon after they've swallowed the mixture they will become drowsy and they'll become unconscious fairly quickly. Their death would be somewhere around about an hour or a little bit longer than that," Professor Dooley said.

"If a patient does decide that they don't want to take the medications they can return them to us."

"In the event that a patient dies without taking the medications, there is a designated contact person for each patient who then has the responsibility to organise the return of the medications to the statewide pharmacy service."

Terri hopes the laws will bring relief to terminally ill patients and their families.

"I think it's great that people who do want to take advantage of that opportunity will be able to," she said.

"A lot of people will hang in there in terrible pain and want to go until the very last gasp, but some people will feel the need to end their lives when they are ready. It's not going to be easy to do, but at least it's there, it's a start."

Terri Eskdale hopes the new laws will help people in a similar situation to her partner. ( ABC News: Jarrod Whittaker )

It is unlikely Mark would have been eligible under the new laws, but if he were allowed access to the drug, Terri believes he would have been able to relax more and enjoy the time he had left.

"I know that he would have had peace of mind to know that if he needed to go, if he felt he'd had enough, he could go in comfort."