Brand name vs. generic medications

The FDA says it's interested in hearing reports of undesired effects when switching from a brand name drug to a generic formulation or from one generic drug to another. Here's what the FDA has to say on generic medications:

FDA requires generic drugs to have the same quality and performance as brand name drugs.
When a generic drug product is approved, it has met rigorous standards established by the FDA with respect to identity, strength, quality, purity, and potency. However, some variability can and does occur during manufacturing, for both brand name and generic drugs. When a drug, generic or brand name, is mass-produced, very small variations in purity, size, strength, and other parameters are permitted. FDA limits how much variability is acceptable.
Generic drugs are required to have the same active ingredient, strength, dosage form, and route of administration as the brand name product. Generic drugs do not need to contain the same inactive ingredients as the brand name product.
The generic drug manufacturer must prove its drug is the same as (bioequivalent) the brand name drug. For example, after the patient takes the generic drug, the amount of drug in the bloodstream is measured. If the levels of the drug in the bloodstream are the same as the levels found when the brand name product is used, the generic drug will work the same.
Through review of bioequivalence data, FDA ensures that the generic product performs the same as its respective brand name product. This standard applies to all generic drugs, whether immediate or controlled release.
All generic manufacturing, packaging, and testing sites must pass the same quality standards as those of brand name drugs, and the generic products must meet the same exacting specifications as any brand name product. In fact, many generic drugs are made in the same manufacturing plants as brand name drug products.

FACT: Research shows that generics work just as well as brand name drugs.
A study evaluated the results of 38 published clinical trials that compared cardiovascular generic drugs to their brand name counterparts. There was no evidence that brand name heart drugs worked any better than generic heart drugs.[1]

FACT: FDA does not allow a 45 percent difference in the effectiveness of the generic drug product.
FDA recently evaluated 2,070 human studies conducted between 1996 and 2007. These studies compared the absorption of brand name and generic drugs into a person’s body. These studies were submitted to FDA to support approval of generics. The average difference in absorption into the body between the generic and the brand name was 3.5 percent[2]. Some generics were absorbed slightly more, some slightly less. This amount of difference would be expected and acceptable, whether for one batch of brand name drug tested against another batch of the same brand, or for a generic tested against a brand name drug. In fact, there have been studies in which brand name drugs were compared with themselves as well as with a generic. As a rule, the difference for the generic-to-brand comparison was about the same as the brand-to-brand comparison.
Any generic drug modeled after a single, brand name drug must perform approximately the same in the body as the brand name drug. There will always be a slight, but not medically important, level of natural variability – just as there is for one batch of brand name drug compared to the next batch of brand name product.

FACT: When it comes to price, there is a big difference between generic and brand name drugs. On average, the cost of a generic drug is 80 to 85 percent lower than the brand name product.
In 2010 alone, the use of FDA-approved generics saved $158 billion, an average of $3 billion every week.[3]

FACT: Cheaper does not mean lower quality.
Generic manufacturers are able to sell their products for lower prices because they are not required to repeat the costly clinical trials of new drugs and generally do not pay for costly advertising, marketing, and promotion. In addition, multiple generic companies are often approved to market a single product; this creates competition in the market place, often resulting in lower prices.

FACT: FDA monitors adverse events reports for generic drugs.
The monitoring of adverse events for all drug products, including generic drugs, is one aspect of the overall FDA effort to evaluate the safety of drugs after approval. Many times, reports of adverse events describe a known reaction to the active drug ingredient.
Reports are monitored and investigated, when appropriate. The investigations may lead to changes in how a product (brand name and generic counterparts) is used or manufactured.

FACT: FDA is actively engaged in making all regulated products – including generic drugs – safer.
FDA is aware that there are reports noting that some people may experience an undesired effect when switching from brand name drug to a generic formulation or from one generic drug to another generic drug. FDA wants to understand what may cause problems with certain formulations if, in fact, they are linked to specific generic products.
FDA is encouraging the generic industry to investigate whether, and under what circumstances, such problems occur. The Agency does not have the resources to perform independent clinical studies and lacks the regulatory authority to require industry to conduct such studies. FDA will continue to investigate these reports to ensure that it has all the facts about these treatment failures and will make recommendations to healthcare professionals and the public if the need arises."
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[1] Kesselheim et al. Clinical equivalence of generic and brand name drugs used in cardiovascular disease: a systematic review and meta-analysis. JAMA. 2008;300(21)2514-2526

[2] Davit et al. Comparing generic and innovator drugs: a review of 12 years of bioequivalence data from the United States Food and Drug Administration. Ann Pharmacother. 2009;43(10):1583-97.

[3] SAVINGS An Economic Analysis of Generic Drug Usage in the U.S., GPhA, September 2011, page 1.

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53 replies. Join the discussion

This is very interesting-thank you Brenda! That said, my doc highly recommended that I take the brand name version (Synthroid) instead of the generic version...

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My doctors, at one of the top thyca-hospitals in the country, had no preference for brand name over generic, but I did. I had done enough research in advance to know I did not want to take my chances with the fillers being changed at any time and/or the generic type being carried by my pharmacy altered at any time. I've also noticed on this message board that those who are on the generic version tend to be on significantly higher doses than those who are on name brand. That indicates to me that the generic may be harder to absorb.

All that being said, I think that if you've hit your target dose, changing to a different drug (be it brand name to generic or vice versa) would be deterimental. Stick with what works, but if you're on generic I recommend you investigate your bottle every time you get a refill to ensure you're not getting something different from what you expect. With my insurance, I pay $20 per month for Synthroid versus a $10 co-pay for generics. I don't consider that significantly more for peace of mind every month.

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I agree with Kat on this one... for T4 (Synthroid/Levothyroxine/etc), it is important to stay on a drug made by the *same* manufacturer.... it can be a generic manufacturer, but because the fillers are different and this can affect how the drug is absorbed into the body, it should be the same manufacturer each and every time you get a refill. The easiest way to do this is to be on a brand name of the drug, because your pharmacist can and might change your generic to a different generic without telling you (you'll know, because the pills will look different, but by that time it is a pain to have to go back to the pharmacy and try to get them to give you the same generic you were on before).

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Well said, Kat and Theresa.

When a medication is especially critical (replacing an organ) and a fair percentage of patients show sensitivity to generic brand variations (i.e. thyca patients), then the broad generic statements won't necessarily hold up. Very few patients pay attention to lack of consistency among generic manufacturers, until they experience better or worse performance with some than others. As Theresa said, doctors take the responsibility for consistency when they prescribe name brand/Synthroid.

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This seems to be an on-going problem for those of us sensitive to any changes. "To save money" I tried a different brand and had an extreme hyper reaction within only a few days, high anxiety, inability to sleep, nervousness, too much energy, mood swings..... With the advice of my endocrinologist I went back to what I'd been taking and went back to "normal" just as quickly. The most recent prescription was filled at a different pharmacy, got all the way home to realize comparing meds that it was not the same COLOR, no matter what the bottle said, so sure enough, they had used a generic. From that previous experience I took it back to the pharmacy and they replaced it with the brand name without a problem after I explained. I think some pharmacists deal with thyroid cancer patients but rarely and assume we are like other thyroid patients who still have a thyroid, for one thing. But, best we all "keep on our toes" that we are getting the SAME medication each time, especially those of us who are the most sensitive to changes.

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I agree. It's best to stick with a single brand or generic by a single manufacturer. For thyca patients the "undesired effects when switching from a brand name drug to a generic formulation or from one generic drug to another" are more significant than for most conditions, and perhaps even dangerous for uninformed thyca patients. I think it would be a good idea to gather up and send to the FDA a record of the undesirable effects reported by the Thyca Support Community. It might trigger a change for the better for thyroid medications -- such as warnings to pharmacies and/or more stringent tolerances for manufacturers. I'm not sure how sending such records could best be done. Do you think thyca staff would be interested in such a project?

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I encourage you to ask the thyca staff. If the information could get to pharmacists, perhaps they wouldn't be as cavalier with generic substitution without informing patients; it could save a lot of unnecessary suffering from not realizing it is something so simple as consistency in formulation.

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My concern about generics provided under a prescription plan is that they can be freely substituted by the pharmacy benefits company(Medco/Express Scripts). We are fortunate with our levothyroxine that we have alternate "brand" names which are almost as low price as generics. In addition to synthroid there is levoxyl and unithroid. I have been taking levoxyl for 12 years and found that it is consistent in its dosage, etc. Plus they charge me the generic co-pay.

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You know, I was just wondering about this. I have been on the generic levothyroxine for months now, but when I changed endos, she wanted me to make sure I got the brand name, and I was wondering why. Essentially they should be the same, right? Apparently not. Now it makes much more sense. Unfortunately, right at that time, I had just refilled my prescript for 90 days of the generic, so in about 20 days, I'll be filling the brand-name prescript. I can't imagine the heart-attack my insurance would have had if I'd have tried to switch right after a refill. Oi.

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I've been on generic levo from day one. It's never been a problem and has always been filled with the same manufactured pill.

Brand name meds are not superior. Some people do better with some inactive ingredients over others, so it's good we have a choice.

FDA wants to know any adverse reactions a person has on any medication.

I have not had any adverse reactions to levothyroxine sodium in the 3+ years I've been on it.

"My concern about generics provided under a prescription plan is that they can be freely substituted by the pharmacy benefits company(Medco/Express Scripts)."

Freely substituted with what?? A brand name levo? As there are no generic levos bioequivalent to one another, so when on generic, you'll always get the same generic.

A pharmacy is not going to run out of generic, it's what they stock. You have a larger chance of them running out of brand name or suddenly deciding they don't want to carry the brand name any longer.

It's easy enough to talk to your pharmacist about.

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I have had zero problems with lack of consistency in generic levo.

They're all equal.

If a person feels better spending more money on a brand name levo, more power to them.

but brand names are not better or more consistent.

my guess, if your doctor wants you on a brand name medication, they have some kind of incentive to push brand name.

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Jani, it's good if you have felt fine on generics. Not everyone does well when the generic manufacturer is switched on them. That's what the point is here. Some of us are very sensitive to the differences. I am certain my doctor is putting my welfare above any incentive.

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I have not done hard research on this issue since I'm sticking with name brand, but this article indicates that there are at least three manufacturers of generic levothyroxine. Any pharmacy can substitute one of these at any time for another without having to inform you, the patient, because the active ingredient in all of them is the same. So the concern over being "freely substituted" is a very valid one.

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I had been on a generic and when I switched endos the new one wanted me on brand name Levoxyl. Her rationale was that unless I was guaranteed getting the exact same generic, made by the same manufacturer, there was a chance that some of the fillers could be different and affect the absorption etc. If you are on a brand name, it is manufactured with the same ingredients and no matter what pharmacy you have your Rx filled, the content of the pill will always be the same. While I had no problems with either, considering how sensitive some people are to small variations (as I have read here), that makes a lot of sense to me. Every profession has it's share of charlatans and frauds, but I really do believe that most medical professionals do care about their patients and any small financial incentive to push a certain brand name would be an unnecessary risk to a very lucrative career. I have read ( I can't remember where and it is too late for me to find it) that it is not recommended to switch even between generic because of the differences in the manufacturing.
When you think about the content of the pills, for example, I take 125mcg. That is 125 MICROgrams (one millionth of a gram)of active ingredient, the rest is fillers. My husband, who is an engineer and has weighed strange things, said that 125 mcg is the weight of a fingerprint. It seems to me that in that case, most of the pill is filler and the active ingredient is a very small component, maybe that is why the different fillers can make such a difference in how the body reacts to the active ingredient.

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No, not any pharmacy can sub. any generic.

Possibly, there were 3 generics at one time, but last info I have read, there are two generics. And those 2 generics have NOT been studied for bioequivalence.

That means, a person on generic can NOT have their generic filled by another generic. Meds MUST be found bioequivalent by the FDA to refill one another.

The only levo. that can refill generic levo (in my instance, Mylan) is BRAND name 'anything'...levothroid, levoxyl, synthroid....whatever.

As far as generics, today, I know of Sandoz & Mylan, no idea what has happened to Lannet (sp ?) I assume that is the 3rd generic.

Anyhow, Sandoz & Mylan, canNOT refill one another because they are NOT bioequivalent.

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I would assume consistency shows in the numbers.

I think its unfair for a medical doctor to arbitrarily decide a patient 'needs' name brand.

It's your money, not his/her.

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For me, consistency shows in how I feel; plus numbers. Just a different approach, since I am very sensitive.

It could be Levoxyl or Synthroid, or a doctor can inform and then trust the patient to stick to the same generic manufacturer and advise them to stay firm when encountering blase' pharmacists. Many patients might end up just requesting brand after some hassles with generic inconsistencies and/or unhelpful pharmacists.

Some sensitive patients order by mail and can't rely on consistency with generic manufacturers. IMHO they would be better off with one of the brands for consistency.

I suppose many of us could be in trouble at any time if a lab has to shut down. It is happening in record numbers these days and frankly that worries me more than choosing a recommended brand or not.

My doctor noted my sensitivity before I did and recommended a brand for consistency while we worked on getting my dose right, since I don't convert T4 to T3 well. I respected his honesty and **WE** agreed to use a brand. It was not a unilateral decision, since - as you say - it is my money.

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I am interested to know how a pharmacy would know what lab produced your generic if you went into a drugstore with a script to get it filled, say if you were traveling, or switching from on site purchasing of meds to mail order or moving and using a different pharmacy? In my case, it is a moot point because I was paying $9.00/month for generic and $14/month for Levoxyl. For a matter of an extra $60/year, I think I will stick with the opinion of the thyroid cancer specialist that I am seeing. Jani, how do you know that the bioequivalence of the 2 generics has not been tested? I am curious as to the source of your info.

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Well, there is more than one individual on this board who has said that their generic "brand" has been changed by their pharmacy unbeknownst to them (until they got home and looked in the bottle). Therefore, it can and DOES happen. If that's the chance someone wants to take to save a few bucks, that is their decision. They just need to be aware that they must do their due diligence every time they pick up a new prescription. It should also be pointed out that the manufacturer of a generic can change the fillers at any time. In that case, the patient would have no idea something different is in the bottle, and that's where the real problems can arise for someone who is sensitive to ingredients.

I'm not sure why you get so contentious with people whose opinion is opposed to you on this issue. You choose generic and that's fine. I choose name brand and that's fine. That's what's so nice about choices. My purpose in posting is to help people, and I believe telling them that they have to scrutinize better if they choose generic IS helping them.

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I once had simvastatin substituted for lipitor and my doctor acknowledged approving it because the pharmacy benefits manager contacted him and said I would save a lot of money and he thought he should "help". We have an understanding now. Anyhow, bioequivalence may not be enough. There may be differences in absorption, fillers, etc. Actually the only problem I ever heard of was with synthroid not generics. Back around 2001/2 they were cited for irregular dosages in tablets. I switched back to levoxyl and never looked back. My plan charges the generic co-pay for it.

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