Some patients say Pharmac's switch to fund a cheaper, generic brand of antidepressant has left them struggling with everything from headaches to serious depression - and are urging the government drug-buying agency to start funding their old meds again.
Last September Pharmac stopped all funding for Effexor XR, the original version of the antidepressant venlafaxine, as well as another brand, Arrow-Venlafaxine - they had been starting to switch people to the new drug for months already.
It now pays for a cheap, generic version called Enlafax XR, which has the same active ingredient and is considered "bioequivalent", meaning the 45,000 New Zealand patients who use venlafaxine should see no difference.
But Heather Williams, 33, believes the brand switch nearly cost her her life.
Williams has taken Effexor XR since 2007 after chronic pain sent her spiralling into depression. The medication helped her lead a normal life as a support worker in Palmerston North.
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But when she was switched to Enlafax in May 2017, she rapidly went downhill.
"Within three weeks, I couldn't function. I was suicidal, I lost all motivation," she said.
Williams posted about her experience on the Facebook page of The Nutter's Club. Dozens of people responded with their own experiences, from headaches to extreme anxiety after the brand switch.
In June Williams went to a walk-in clinic and demanded a prescription for Effexor. But the improvement on the old meds was only slight. "I was still in a pretty bad, bad state. I really struggled for quite a long time."
Williams tried to take her own life twice and ended up in hospital. Her GP upped her Effexor dose to the maximum, which has helped although she's "not completely stable yet".
She is paying $55 per month for the unfunded Effexor, but worries many people won't be able to afford that.
From June to the end of November 2017 - the latest for which data was available - 116 people formally reported to the Centre for Adverse Reactions Monitoring they had had at least one bad reaction to taking venlafaxine.
The numbers were not broken down by brand but most would have been taking Enlafax as the other brands were being phased out.
During the same period in 2016, there were just nine reports of bad reactions.
In the latest numbers, 58 people said the drug wasn't working properly, while 13 had suicidal thoughts. Nausea, fatigue, headache and anxiety were also reasonably common.
Medsafe confirmed it was aware of complaints about Enlafax.
"We are sorry to hear that patients have been having difficulties with this medicine," Medsafe general manager Chris James said.
"Generic medicines are considered to have the same benefits and risks as the innovator and are tested to show that they are bioequivalent."
James said it was not unheard of for people to report adverse reactions when Pharmac changed a medication - such as the switch to a cheaper version of the antidepressant fluoxetine in 2014. In that case, patients and their GPs had successfully changed their dose or switched to a similar medicine.
Professor Paul Glue, head of psychological medicine at Otago University, said it was common for people to report a generic product had new side effects or was less effective.
It was hard to know whether those reactions were caused by a placebo effect or something else. Glue, an inpatient psychiatrist, prescribes Enlafax regularly and has seen no problems. "But I see people for a relatively brief period of time - most of their care is happening in the community."
Patients struggling with Enlafax should talk to their GP or a psychiatrist, he said.
Pharmac chief executive Sarah Fitt said generic medicines were a way for Pharmac to keep up with demand for new drugs.
"Moving to sole supply of Enlafax XR created $5 million per year of savings. Pharmac is able to use these savings to fund more medicines for more people."
Pharmac was in regular contact with Medsafe, the government authority that monitored adverse reactions. It would take any action Medsafe deemed appropriate, Fitt said.
In exceptional circumstances Pharmac considered funding patients for non-funded medications, she said.
"People should work with their healthcare professional to see if this option is appropriate."
Earlier this month venlafaxine user Helen Leggatt began a petition at Change.org, accusing Pharmac of "penny-pinching" and asking for Effexor to be funded. Almost 1000 people have signed.
Williams has a simple message for Pharmac.
"Stop telling us that it's the same and it's effective- we know it's not. We're not making this up," she said. "We are vulnerable anyway being stigmatised with mental illness - then we have to try and prove we're not telling lies. We've been completely invalidated."
Where to get help:
• LIFELINE: 0800 543 354 (available 24/7)
• SUICIDE CRISIS HELPLINE: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• YOUTHLINE: 0800 376 633
• NEED TO TALK? Free call or text 1737 (available 24/7)
• KIDSLINE: 0800 543 754 (available 24/7)
• WHATSUP: 0800 942 8787 (1pm to 11pm)
• DEPRESSION HELPLINE: 0800 111 757