Can different brands of the same medication really have such a difference in effectiveness?

[ImJustATeenageGreboBaby]

Or should that be efficacy?

Anyway. I take tranexamic acid to relieve my heavy periods, which I buy online. It's always worked very well. A few months ago I bought some from a different online pharmacy as my usual place was out of stock. They sent a different brand, same medication and strength though.

Since I started using that batch, basically it hardly seemed to work at all, it took longer for bleeding to ease off and after I stopped taking the medication (you're only meant to use it for 3 days) the bleeding just started up again really heavy . Also every time I used it my period would drag on and on with unpredictable lighter bleeding for well over a week. At first I assumed it was my body, maybe peri hitting or something. But it ran out last month, and this month I've started a new pack from my usual pharmacy/brand, and it's working exactly as it always used to. Completely different experience!

Can this really be down to a different brand? I'm assuming medication is tightly controlled so it can't be weaker from brand to brand, but then what could it be down to?

both in date?
identical active ingredirnts?

According to pharmacists with whom I've discussed this around antihistamines, yes, different brands can behave very differently. Apparently it's something to do with the carrier agent.

Yep, exactly the same active ingredient and well within date.

Oh interesting, I might still have some of the crappy batch at the back of a drawer so could possibly check the carrier agent.

I’ve always been told that Cerelle and Cerazette are exactly the same, but I bleed almost constantly on Cerazette and have no issues on Cerelle.

I would worry that if you are “buying” prescription medication online that you might have been sold something that is now what it says.
However, if it is a legitimate pharmacy and you have a valid private prescription then it could possibly be as said above

I take medication for my bladder and have definitely noticed that one brand just doesn't seem to work for me but the other one does!

Yes. I was prescribed omeprazole for years and used to get various generics dispensed. Two of them brought a complete return of symptoms. I saw my GP and she told me her mother had had a similar thing and from then was able to specify a branded version for me to guarantee efficacy. She explained it was the carrier agent that was the likely suspect.

I was going to say the same about antihistamines as my dc complain if I get the cheaper Tesco version for their hay fever as they say it doesn’t work like Piriton.

Faked pharmacy websites selling counterfeit medicines is a problem. You could check the website here
https://www.gov.uk/check-suspicious-online-medicine-seller

Although many people have cited pharmacists and gp’s there is also the “reverse”placebo effect compounded by confirmation bias which could play a factor. It could well be that because it’s not your usual brand, psychologically you don’t think it will work the same, so it doesn’t. There have been studies into this nocebo effect.

I say "buy" as shorthand but what I mean is pay for a private prescription, it involves an online pharmacist consultation.

The website checks out as legitimate so I don't think it's dodgy as such, just that for some reason this brand didn't work for me.

Possibly but tbh I hadn't really given it a second thought until it didn't seem to be working, and then I assumed it was down to my periods getting heavier due to my age. It wasn't until I got a new batch that worked fine, that I started wondering if the brand could have made a difference.

Levothyroxine absolutely does differ by brand and enough people have struggled with different brands that we're supposed to be able to request a specific brand (that works for us) be prescribed by Drs.

Yes

my dd has thyroid problems and takes Levothyroxine. Her prescription states her brand. T is apparently very common with levothyroxine.

This is my understanding too; the way the active ingredient is carried and therefore absorbed by your body will affect people differently. I guess for most people the difference is small but for some individuals may be significant.

Yes I’m on a mh medication, I was totally oblivious to the brand, but last month I started getting weird side effects (heart problems proven on a 48 hour halti monitor) and less efficacy. Switched to the other brand and within weeks the issues are gone. My doctor says some medications are less pure than others and not as well made, it’s apparently well known and yet plenty of people still tell you it’s all in your head. 🙄

I had the same thing happen with an antibiotic that I had to take for six weeks. The second month I got it from the pharmacy they gave me a different brand and it caused diarrhoea.

It’s definitely a thing. I am hyper mobile and have taken Zapain co codamol for years. When there was a shortage and I was given a generic version, I thought nothing of it. I expected it to work exactly the same.

It absolutely didn’t!

There are certain medications such as antiepileptics that have to be prescribed by brand as it is well recognised that efficacy can vary between brands

My Mum has taken epilepsy medication for years. A while ago the pharmacy started to give her medication made by a different manufacturer. Shortly afterwards, she really started to struggle with her medication, feeling it wasn't supporting her until the next dose. GP had no ideas. After a few months, she asked him if it could be a different brand, he looked it up, no known problems. However, she insisted she wanted a batch of her previous brand, and yes it made all the difference. It's actually on her notes, she has to have a certain brand now.

I definitely found this with Levothyroxine. One brand seemed to have no effect whatsoever and I complained about it. GP insisted that it wouldn’t have made a difference, but reissued my prescription anyway so I could find a pharmacy with another brand.

Shortly afterwards I saw online that the first brand manufacturer had lost their license to produce this medicine due to concerns about its efficacy after many complaints.

They seemed to crumble in my mouth, so clearly weren’t as dense as they needed to be, which maybe meant they had less of the medication in them?

Same re thyroid medication - felt like death when I was given a different brand, like I'd not been taking anything at all, all the awful symptoms returned. I only get 2 months at a time and within a couple of weeks felt much better on my usual brand.

Yes I believe they can. I had a medication once and they didnt have the usual brand in so gave me a different one. I told my GP that for some reason they seemed much less helpful and he said it can happen and they would make a note to not give that brand again.

There are some medicines that have to be brand prescribed, for example levothyroxine and some anti-epileptic medicines.

Most other generic medicines (are supposed to) have the same efficacy and bioavailability as the brand originator demonstrated before they are licensed, but there have been incidences of data falsification in the past, and sometimes batches are withdrawn because they are defective.

Separately to this, the “filler” will differ from brand to brand, which may account for sensitivity reactions.

If you are worried about lack of efficacy or unusual side effects, you can report them here. It’s for everyone, not just healthcare professionals. This helps hold the manufacturers to account. https://yellowcard.mhra.gov.uk/