Friday, December 18, 2009

Do Generics Work as Well as Name Brands?

It's my first night of vacation! I saw my last patient today and then started pulling the pictures off the walls in anticipation of my move. I ran over to see the new place, and it still needs insulation (it's on the floor), paint, and carpet. And doorknobs might be nice.

So we're expecting quite the snowstorm here. I'll let you know how it goes tomorrow, but the current forecast is for up to 20 inches. It didn't take me long to float from the weather to the health section of the New York Times, and here's an article by Leslie Alderman about generics versus name brands.

Are generics as good as name brands? I don't have any studies, I'm purely running on anecdotes, but this is my thinking: Usually. When I was resident, I learned that 15% of the time (and this isn't science, I don't think, I believe it's someone else's anecdote) generic nortryptiline doesn't work when name brand Pamelor does. So I've always asked patients to start with Pamelor....I don't use it much anymore....because who wants to spend 6-8 weeks on a medication trial and have someone not respond only to realize they were in that small group of patients who are sensitive to the brand.

Other meds: I've had a handful of people complain about generic Prozac-- fluoxetine. It's not as effective for them, or they have more side effects. Alderman's article talks about Wellbutrin XL and I didn't even realize that the XL form now has a generic. Sometimes people want the name brand.

So what do I do when a patient specifically requests the name brand? I give it to them: if they are right, then they are right. And if they simply believe that they won't respond to the generic, because there are people who say "Generics don't work on me," well, then there's power to such beliefs, and I just want my patients to get better.

What do you think?


Sunny CA said...

I am just 1 person with 1 drug, but for me it made no difference, but my doctor thinks it does (or is in bed with the drug company). My endocrinologist writes me prescriptions for Synthroid (levothyroxine sodium) that say "no substitutions; this brand only". My druggist on my request gives me the generic. There is no difference for me, and my doctor can't tell the difference when he does blood work. The doctor has a study which shows Synthroid to be superior to the generic posted in his office. I think the study must have been underwritten by Abbott and I do not trust the study nor him as a result of hawking Synthroid.

Judy said...

Such an internal struggle for me when I go to purchase advil or tylenol and see the store brand at less than half the price! Geez, to date I end up with the advil or tylenol.

Pissed said...

When I started celexa, I had my physician explain it to me wonderfully (was seeing a counselor at the time and went to my general doc for meds- my general doc is heavy in psych though, and I and my psychiatrist friends highly recommend her!). She told me that there were some minor differences in the way Lexapro and Celexa were chemically engineered, and that some of those differences were a) what enabled celexa to be sold, and b) also caused some different side effects and effectiveness. She started me on Lexapro for 6 weeks(free handouts wee!) then wrote a prescription for Celexa. She told me that if after starting the Celexa, I found it to be different than the Lexapro, she'd be willing to keep samples headed my way.

Still on Celexa and loving it.

moviedoc said...

I'm skeptical: How is it that the generics always seem to cause more side effects or to be less effective? Why does it never seem to be the other way around? Remember the placebo effect? And what about all those people who swear by drugs purchased outside the US?

If a generic is less effective, it may still be cheaper at a higher dose. As for anti-epileptics, don't the neurologists go by serum levels for many of them anyway?

sara said...

Not to sound too conspiratorial (and I take some generics, some brand - typically based on cost and/or availability of generic) - but legally speaking, the generic form of a brand drug does not have to be the same. The FDA requires only a plus or minus 20% bioequivalence of the active ingredient -- that's a major difference, and probably explains why generics seem to work for some people while only brand works for others -- for that matter, some generics likely work much better then others. There's plenty of anecdotal literature out there - wellbutrin generics seem to be a big one.

The Hatch-Watchman act of 1999 allows the FDA to use that plus or minus 20 percent figure to determine blood serum bioavailibity (amount of active ingredient of the drug in the blood) over the perio of time to be within +/- 20% observed when the brand drug is ingested.

That's a huge amount of variability!!!

moviedoc said...

Does that +/- 20% bio-availability limit not apply to branded drugs as well as generics?

Anonymous said...

I'm a pharmacist & sit on the P&T committee - the hospital committee which determines which drugs will be purchased & by which manufacturer.

The person who mentioned the 20%+/- variability in blood concentration doesn't realize the blood level is often not of any concern. Since we are concerned about brain levels of antidepressants, blood levels are not followed (with the excetion of a few - lithium being one). So, once a pt reaches "steady state" - often 3 weeks with antidepressants, blood levels are meaningless since the blood brain barrier regulates how much gets into the brain & how fast.

A generic manufacturer must submit significant data for the drug to be bioequivalent to the brand or the first product on the market. This data includes dissolution, rates of absorption, elimination & penetration into the target tissue (ie - intraocular fluid for glaucoma drugs rather than plasma levels as one example). They must also substantiate how long the levels stay within therapeutic range so dosing is the same as the initial product.

There are drugs which are not interchangeable because they have such a narrow therapeutic range - digoxin, warfarin, carbemazepine are a few. That doesn't mean the branded drug is required (in fact, I've not seen Lanoxin - the brand of digoxin in 20 years). It only means the pt cannot be switched from one brand to another without doing lab tests to be sure the blood levels are stable (these are drugs in which blood levels reflect therapeutic effect or toxicity).

Some drugs have such variability within the brand itself that the therapeutic effect is too unstable. Elavil, a tricyclic antidepressant was one of these drugs. The brand was removed from the market because the generics were more stable products.

The levothyroxine products (Synthroid, Levoxyl, l-thyroxine) are very inherently unstable chemicals. Lactose was added to these products to promote stablity and processing. However, 10 years ago, lactose had to be removed by an FDA mandate & now they are unstable & non-interchangeable. However, if you are admitted to a hospital - no matter which one you take, you will be put on levothyroxine & the levels will be followed & kept stable - we don't keep every brand because its too expensive. Its easier to retitrate you on the generic.

People confuse things like Lexapro & Celexa as the one commenter did. Lexapro has one side chain which is different from Celexa. The sole purpose in doing that was to keep a branded product on the market to compete with other branded products when the Celexa patent ran out - the side chain neither adds to nor takes away therapeutic effect. That allowed the company to have one generic (citalopram) to compete in the generic sertraline, etc business & one branded product to compete in the other market. Similar marketing tools took place with Claritin, Prilosec & others when they went off patent.

There is no one "right" answer to this question. From a pharmaceutical standpoint, very few generics are any different from brand names & particularly antidepressants. Few people even know that most of the generics are actually made by the same company & sold to generic firms to be marketed. When the drug has a narrow therapeutic index, we make sure the brand is not changed. If we must make a change - the physician is informed so testing is done to keep the patient stable.

This is what is being talked about when we get into decreasing medical costs. These "me too" drugs and bad marketing practices increase drug costs & medical costs unnecessarily.

Anonymous said...

Dear Anonymous pharmacist,

Thank you for your cogent explanation about the difference between many brand and generic medications.

A comment on your final paragraph:

"These "me too" drugs and bad marketing practices increase drug costs & medical costs unnecessarily."

'Me too' medications are in fact different from the ones they imitate. And thankfully so. My patients and I are so grateful for the continued development of new medications. This gives patients choice.

Too many patients have indeed 'tried them all.' So when a new medication is enough different to get FDA approval, that new medication often helps them when others had failed to do so.

Ally said...

I found plain old lamotrigine to be much less effective than Lamictal, and my psychiatrist assures me that she has seen this with quite a few of her patients. Of course once a generic comes on the scene, the price of the brand name goes way up. Luckily she gives me coupons from the manufacturer.

Anonymous said...

Regarding the Anonymous Pharmacist's comment on citalopram (celexa) vs. escitalopram (lexapro): There isn't a 'side chain' added to lexapro.

Citalopram (like all organic molecules) comes in a (racemic) 50/50 mixture of left handed (S) and right handed (D) versions of the molecule. The trick behind lexapro is that it contains only the left handed version of the molecule (thus s-citalopram ie escitalopram). Plain old celexa contains the 50/50 mixture, and this is why the dosing of lexapro is generally 1/2 that of celexa.

So - there's no side chain difference, just mirror images of the molecule. Your central point that this was just for patent extension on celexa is spot on, I just wanted to quibble about the pharmacology.

Anonymous said...

Hi, I found this post very interesting. I wanted to ask: do physicians who prescribe antdepressants are concerned about the complaints from patient that the generics don't work as well? Is it a concern when you prescribe a drug?

Does it bother psychiatrists when their Rx are switched to generics without their control? Thanks!

Anonymous said...

I just found this and had to comment. I've been on Wellbutrin XL for a couple of years. I have tried to take the generic version four separate times because the name brand is so expensive.

Each time I had such bad experiences. I went through tremors, nausea, headaches, crying for no reason, crying pretty much all the time, and feeling like I was "losing it." Once I started back on the name brand for about a week and a half everything calmed down. It was like I woke up and everything was normal. Almost like seeing once you've put glasses on.

I wish so bad that the generic could work. It's only $7 compared to $50. But after going through that each time, I'm just going to stick with the name brand.

Now I'm a little worried about being able to quit this. I don't take anything else. I rarely take asprin or ibuprofen. I only drink a glass of wine maybe once every other month. Will I have to take this for the rest of my life? If it means having clarity and feeling normal, then I definitely will. It makes me sad that my body can't manufacture whatever it is that's missing.

People aren't very understanding when it comes to meds like this. I went on it after my divorce, and I've tried to hide it from people I've been in a relationship with. I've also told them about it once things have gone on for awhile and seem serious. Once they find out.. they are afraid I'll end up crazy or something. But whatever. If I can't be honest with someone then what's the point.

Anyway.. just wanted to say that the generic has to somehow be different from the name brand if I had consistent reactions to switching several different times.

Thanks :)

Anonymous said...

I don't understand why people can't workout the insight on brand vs. generic.

When say the patent ran out for Zoloft, and people can now not get ripped off and can buy the generic[Setraline].

It is exactly the same, in dose and in every other way. But there are all these people bitching that they don't work or whatever.

Well I can tell you, it won't work because of something like the placebo effect. People think "oh it costs less, so it can't possibly work".

It doe's not work because they are causing it to not work. If you swapped the brand for the generic without these knowledge, it will work perfectly. Mystery solved, weak people that are psychosomatic.

Anonymous said...

"It doe's not work because they are causing it to not work. If you swapped the brand for the generic without these knowledge, it will work perfectly. Mystery solved, weak people that are psychosomatic."

The problem with this assessment is that many people have actually had their meds changed from pharmacies etc. without them knowing/noticing it themselves. And then they have a bad reaction, or their original symptoms comes back, and not until months later they notice that they have been given a different drug, and that's when they understand exactly why; namely that they do not have the same reaction that they had on their original drug.

Other than that, calling people weak because they are affected by the placebo effect is just very uninformed. Everyone can be affected by a placebo effect - even you. It has nothing to do with being weak, it's just human psychology.