Phenobarbitone (15 mg and 30 mg tablets): Brand change

Affected product

API, the supplier of the currently funded ‘PSM’ brand of phenobarbitone tablets (15 mg & 30 mg), has closed its New Zealand manufacturing plant and is no longer supplying product in New Zealand.

Because of this, the funded brand of phenobarbitone tablets (15 mg & 30 mg) will be changing. 

Chemical: phenobarbitone
Presentation: 15 mg
Brand: 'PSM'
Supplier: API
Pharmacode: 765481

• Stock expected to run out in October 2023

Chemical: phenobarbitone
Presentation: 30 mg
Brand: 'PSM'
Supplier: API
Pharmacode: 439886

• Stock expected to run out in July 2023
• To be delisted 1 December 2023

Unaffected products

This brand change only applies to the 15 mg and 30 mg tablets. It does not affect parenteral phenobarbitone, phenobarbitone powder or injections. 

Alternative product

The Noumed brand 30 mg phenobarbitone tablets will be funded from 1 July. 

Tender announcement including the 30 tablets

Medsafe datasheet for phenbarbitone pamphlets [PDF](external link)

The 15 mg tablet is still undergoing Medsafe approval. There is enough stock of the current brand (PSM) to last until October 2023. We will provide an update closer the time with more information about the 15 mg strength.

About phenobarbitone

Phenobarbitone is mostly used to treat epilepsy. Approximately 400 people take it.

It is a category 1 antiepileptic agent according to the UK's Medicines and Healthcare products Regulatory Agency (MHRA).

MHRA's advice on antiepilepsy agents(external link)

People who take phenobarbitone tablets

We know that changing brands of phenobarbitone is not ideal. Unfortunately, with the closure of the manufacturing plant for PSM phenobarbitone tablets, there is no choice but to change brand.

We are working to support healthcare professionals and you as best we can, while ensuring New Zealanders can continue to receive funded access to phenobarbitone tablets.

If you take 15 mg or 30 mg phenobarbitone tablets for epilepsy, you will need to visit your GP twice to discuss changing brands:

• About 1 month before you start taking the new brand of phenobarbitone
• About 1 month after you start taking the new brand of phenobarbitone.

You won't need to pay for these appointments. Pharmac will cover your GP visit payment. Funding is available until the end of December 2023.

The experts on our Neurological Advisory Committee have recommended a monitoring programme to help you through the change. You will need to get 4 blood tests so your GP can monitor your progress.

You'll need blood tests:

• 3 weeks before you start taking the new brand of phenobarbitone tablets 
• the same week you start taking the new brand (but before you start taking it)
• 4-10 days after you start taking the new brand
• 1 month after the brand change.

These tests will check the concentration of phenobarbital in your body. You will not need to pay for these tests. If you can't get to a collection site where these tests are funded, Pharmac will cover the cost. 

Health Navigator resources will be available by later this month. 

People who prescribe phenobarbitone tablets

We ask that you alert anyone taking phenobarbitone tablets for epilepsy to the future brand change. Book them in to see you in June. 

If someone who is taking phenobarbitone is pregnant (or could get pregnant), get timely neurologist advice to inform a management approach and refer to advice in HealthPathways. 

They will need to visit you twice – once before and once after the brand change. Pharmac will fund the patient co-payment for these appointments. The reimbursement of waived patient co-payment and laboratory fees will be available until 31 December 2023.

Pharmac’s Neurological Advisory Committee have advised that you will need to carefully monitor people taking phenobarbitone tablets when they change brands. 

This includes organising serum testing for your patients. Where your patients can't get to a collection site where this test is funded, Pharmac will cover the costs for the serum testing.

Record from the Advisory Committee's discussion of the phenobarbitone brand change [PDF, 270 KB]

He Ako Hiringa has developed resources to support you as your patients make this transition. It includes more information about phenobarbital serum testing.

Pharmacists who dispense phenobarbitone tablets

We ask that you alert anyone taking phenobarbitone tablets to the future brand change. Recommend that they book in to see their GP in June. 

We will update this page with more details as we can.

Who to contact

If you take phenobarbitone, please talk to your GP or pharmacist. Pharmac cannot comment on anyone's individual clinical circumstances. Your GP or pharmacist know you best.

If you have other questions about this brand change, email enquiry@pharmac.govt.nz