“Our son was taking his medicine when, all of the sudden, he started showing signs that he was slipping and becoming ill again. My first thought was: ‘He’s stopped taking his medication.’ That’s what his psychiatrist thought too. But it was something else entirely.”
This email from a concerned mother is one of several that I’ve received about a problem that may impact individuals who have been diagnosed with a mental disorder and take anti-psychotic medication.
The mother’s adult son, Phillip, had been doing well on an anti-psychotic drug for several years. Diagnosed with bipolar disorder in his early twenties, Phillip had suffered several mental breakdowns until his psychiatrist found the right medication and dosage to help him achieve clarity without causing severe side-effects.
People react differently to medications. Some do well on one brand, others may react horribly. I do not endorse any specific medications. But this story happens to be about Zyprexa, which was developed by Eli Lilly and is based on olanzapine. When Phillip began taking Zyprexa, his mother said he suddenly became “his old self.” His mood swings stabilized. His thinking cleared and he was able to get a full-time job and move out of his parents’ house. In her words, it was a miracle.
In her email, Phillip’s mother told me that her son was diligent about taking his medication because he knew what could happen when he wasn’t medicated.
“He didn’t want to lose everything that he had worked so hard to achieve.”
So when Phillip began showing signs of mania and depression, his doctor and parents became concerned. ”
“We couldn’t figure out what was happening because we knew he was taking his pills. It was as if they had stopped working and that terrified us.”
His doctor suspected that Phillip’s body had developed a tolerance or immunity to Zyprexa. Perhaps the drug’s usefulness had run its course, he said. But when Phillip became so sick that he had to be hospitalized, he responded well to Zyprexa.
What was going on?
It was at this point that the family realized that Phillip’s pharmacist had switched him from Zyprexa to a generic form of olanzapine. This is because Lilly’s patent for Zyprexa ended in October 2011, making it possible for other companies to issue much cheaper copies.
“We thought generics were the exact same drugs, but they aren’t.”
In Phillip’s case, the generic was not as effective. Once his doctor increased the dosage, Phillip was able to return to his normal lifestyle.
Of course, no one is as unhappy as Eli Lilly is about the use of generics. In 2010, Zyprexa’s worldwide revenues were more than $5 billion, accounting for nearly 22% of Lilly’s full year sales. Since 2003, Zyprexa consistently had revenues of more than $4 billion. Which is why generic drug manufacturers were quick to begin copying it when Lilly’s patent ended last year.
Generic manufacturers must have approval from the Food and Drug Administration that shows the active ingredient in their product is approximately the same as that of a brand name. However, two drugs that are considered to be “pharmaceutical equivalents” when they contain the same chemically active ingredient(s) still may work differently.
Here are a few reasons why:
1. the inert ingredients added to the generic drug might be different from the original.
2. the plants used to make the ingredients may vary in quality by batch and manufacturing methods. According to a New York Times article, nearly 80 % of drug ingredients used to come from plants in Western Europe. Now more and more manufacturers are using plants from China, Japan, South Korea, India and Eastern Europe where they can be produced more cheaply. These sources do not necessarily meet FDA standards yet they continue to be used.
3. in oral drugs, capsule content may be 7% over or 7% under the non-generic pill. This means in a 100 mg capsule, the active ingredient –olanzapine — my be as low as 93 mg or as high as 107 mg. Some persons with mental disorders react to slight changes in their drugs’ potency.
4. generic manufacturers have been known to make changes to the formula that they are using after their drugs are approved by the FDA.
My good friend, Judith Robinson, a mental health advocate and NAMI leader in Miami, was one of the first to tell me about how critical dosages can be. Her son, Jeff, needed exactly 12.5 milligrams of Zyprexa. If he took more, he became droopy. If he took less, he became anxious. The dosage had to be percise.
I want to thank Phillip’s mother for alerting me to the problem that some generics can cause for patients who take Zyprexa now that it is off its patent. I have asked several psychiatrists if they have seen similar cases. Several told me that they had. One told me:
“Most generics work fine, but if a patient begins showing signs of distress, checking the generic should be the first step everyone takes.”