Dont know but I take generic and I feel fine. I'd be interested in other responses too.
My Endo Dr told me he preferred Synthroid over generic due to the fillers in the generic brand. He said alot people do not adjust to the fillers in the generic therefore they have more symptoms, but again, this what he told me. I am sure alot of people do well on generic. Everyone is different and reacts differently to meds.
i have been on both on and off for 10 + years andi can't tell a difference. i think the only difference is the name its the same exact stuff it is mostly for people who can't afford a 15 dollar prescription like me i go to walmart n get levothroxyn and its only 4 dollars. but any ways just thought i would add that
My surgeon put me on generic levothyroxine after my TT. When my endo found out I was on the generic version, he rolled his eyes and immediately prescribed synthroid and I have been on it ever since. I have to say, I have had better luck on synthroid, but can't say if it is because of the brand name or maybe an increased dosage, I can't remember which came first.
The brand names have more consistency in dosage and ingredients, according to what I have read.
There are rules and standards that have to be followed in the manufacture of drugs.
Brand name thyroid drugs all have levothyroxine in them, but the different brands use different fillers. That is how they can get around the patent Synthroid has.
Brand name drugs are held to a stricter requirement for the amount of active ingredient in each pill, and the shelf life of the active drug. Brand name drugs are allowed 5-10% +/- variation from what the label says to what the drug measures fresh and at end of shelf life.
Generics are allowed a variation of 25%, plus or minus, and there is no guarantee that the pharmacy will stock the same generic from month to month. So, the fillers in the generic may change because the manufacturer has changed. Several companies make generic Levothyroxine, but there is no set formula for what the fillers must be.
You have a better chance of keeping your dosage and your hormone levels constant by avoiding generics.
I'm on a few generic medications. Neither my GP nor my Endo will allow me to take generic thyroid meds.
I know synthroid is used for cancer supression because it is more consistent- generic may use different fillers. I have friends with hypothyroidism, and take generic. Cancer survivors need their levels supressed and consistent.
I have been on both and I have to say Levothyroxine I felt tired and crappy. I did not menstrate while taking it. Now that I am on Synthryoid i have been symptom free and and regular cycles!!! I am definitely an advocate for brand name!