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Q+A : Finasteride and Dutasteride

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Welcome to the hair loss show where two of australia’s leading hair restoration surgeons dr russell knudsen and dr vikram jayaprakash discuss issues relating to hair loss and the medical and surgical treatment of hair loss in both men and women hi everyone and welcome to the hair loss show episode 83 my name is dr vikram jayaprakash i’m dr ruslan hunson

Welcome right and today we’re going to go through a couple of questions uh that have been sent through to the channel we thought we’d we’ve been asked this in in a variety of different uh manners so we thought we’d just go through that and really um very straightforward but let’s let’s go through the questions generally about finasteride uh the first question

Is if you go for a higher dose and come back on a low dose after a while would you lose ground on finasteride so that’s i mean basically someone’s taking for example a milligram a day and they’re stabilizing their hair loss and then they decide to go down to three milligrams a week which is what we generally is our starting dose are they gonna lose ground okay

Well this happens all the time in our practice because as you’ve probably heard from our other episodes we rarely prescribe seven milligrams a week so we often have patients come to us either on seven milligrams a week or almost nine milligrams a week because they’re taking seven lots of a quarter of a five milligram tablet which if it was accurate would be

8.75 milligrams which in my opinion is way too much so remember the key factor here is how long the finasteride stays in the body which is much longer than a day so that’s the reason we do believe in micro dosing and customized dosing that people are going to respond differently to it but in general we have not seen any deterioration in the quality of people

Go from seven milligrams for example down to three milligrams now that said that’s not a black and white rule over time because if you look at the original trials with the one milligram per day at one year 86 percent of people were stable at two years was 83 percent at five years of 64 that’s not the drug stopping working that just means that it slows them

Down without necessarily stopping it in its tracks so we don’t have a cure right so basically you’ve got to understand that for some people there’s a bit of leakage but i still think a 64 hit rate at five years in is a pretty good hit rate so generally speaking that would also be true in our experience those same 64 percent of people would be fine at five years

Using three milligrams a week using seven milligrams a week you’re either completely blocked or you’re not um it may be the figures are something like fifty percent of ten years it’s hard to know yes but if you uh are using um at a higher dose and want to come to a lower dose in our opinion as long as you’re using a reasonable amount that’s not a half a milligram

Work for example or a milligram a week as long as using two or three milligrams a week you should be fine now even though this question is about finasterides and it’s an interesting question that also applies to minoxidil because what we discovered over time uh the first product into the marketplace for minoxidil was two percent and then they bought in a five

Percent because of the five percent is obviously it’s a stronger dose but it also has a more stimulatory effect but what they found over time that there is the end result wasn’t necessarily better you just got to the end result faster if you use the five percent which raises the possibility uh that for many patients who are effectively on five percent um that

They could then swap down to two percent later on this has been proven to be true for many patients they could swap down to two percent um and still maintain the effect because they’ve got the full effect and now you’re just maintaining the effect and you don’t need as much to do it so for people that again that are looking to minimize the amount of medicine

In their system it’s feasible that if you’ve got a good response in the first year on five percent and you’re happy with that it is feasible that you could use two percent and maintain that benefit so that’s interesting so let’s let’s go back to finasteride because there’s a couple of points that you you raise that i want to unpack a little bit more which was

First of all is this concept of uh half-life all right because some of the time sometimes i get people asking oh listen i don’t understand you know you say one milligram three times a week because you know it lasts that length of time in the system but then hang on if i look up the data for finasteride the half-life is only eight hours and there’s a difference

Between that because what what that means is that the level of finasteride in the bloodstream drops by half at eight hours but that’s pointless because it doesn’t matter what the level is in the bloodstream it’s what the effect is on the enzyme on the five alpha reductase in the hair follicle correct so that is longer lasting yeah well that’s the original data

Was published when they released the medicine in 1998 and they were very careful to hide that data after that for reasons i’m not sure but um you know the the data originally that i saw suggested that the half-life was 30 days meaning that the the tissue level of finasteride dropped to half its its peak level after 30 days in the system that’s after a single

Dose by the way so if we if we say look testosterone gets converted into uh dihydrotestosterone uh by the five alpha reductase enzyme what we’re saying is that finasteride what it’s doing is it’s blocking that enzyme what’s what it’s doing essentially is making it inactive and one tablet is effectively making that molecule of that enzyme inactive for 30 days

Now it’s there are multiple enzymes in the body so it’s not just what’s not just but the other and the other issue of course is that and it might be effectively a permanent block of that particular enzyme but the body makes new enzymes all the time and that’s a critical factor so that you understand why you should take it more frequently than once every 30 days

So your body is continually making enzymes so you should see the finasterides mopping up new enzymes taking them out of action and that’s really what that’s really what the whole goal of the therapy is to take the enzymes out of action now finasteride takes about two thirds of the five alpha reductase out of action so for some people who haven’t got very elevated

Levels of enzymatic activity in the hair that two-thirds block is enough to keep them happy at five years for example that’s just 64 percent of people at five years that are still stable which is the but if you have the higher level of enzyme and the two-third drop doesn’t take you down quite far enough um that’s the people are still leaking slowly but it raises

The point that we’re not trying the goal of therapy is not to try and bring this down to zero no you know we’re not trying to because again once you do that once you bring it down to zero potentially you can have other effects in the system yeah and we’re really trying to treat the hair and not to obliterate the whole system so it’s about getting that threshold

Level sweet spot correct which is individual for one person as it is for us and why we talk about customized correct yes so it’s about finding that that right dose but it’s er you know half-life is important but not necessarily in the case of you know why you don’t that’s why you don’t need to take the drug every eight hours for example because you’re not worried

About what the blood is if if the half-life blood level was for an antibiotic at eight hours you’d be taking it three hours three times a day that would be your three times a day antibiotic and that’s clearly not the way finasteride was ever prescribed so the prescribing frequency has never been related to the blood level good right that’s good so that answers

That question that’s only the first one all right so let’s look at the next one which is this is a very interesting tricky one i really want to know uh that if i apply avedak capsules topically will it work and regrow hair as a topical deuteride without side effects so we’ve talked about uh topical finasteride this is this is um referring to topical dutasteride

But more so about taking average capsules and applying it uh topically and i’ve had this question a few times about people making up their own uh topical medications using uh oral medications what are your thoughts on that okay look we you know that if you’re using finasteride which doesn’t come as a gel capsule with liquid inside it that you’re not going to be

Able to do this without dissolving it in the solvent yes and then getting our concentration uh because the dutasteride comes as a liquid-filled gel capsule the theory of the patients of course is that they just prick open the dutasteride apply it to the scalp and it it absorbs down to the hair follicle and does its thing and because it’s not being absorbed

Internally it’s not going through the body and therefore it’s not going to create side effects that’s the theory now the two problems with the theory of this number one is that the formulation inside the capsule is meant to survive the gastrointestinal tract not to be absorbed through the skin and the skin has a very specific filtration system for allowing

Molecule size in so this is one of the the magical developments for topical therapies over the years is being able to find a way to get through what we call the skin barrier to get an active ingredient that is a large molecular size in through what from whatever better word is the sieve of the skin that protects uh from large molecules getting in so there’s no

Guarantee that pricking open the capsule and the formulation that you’ve got if you detasterate is even going to be significantly absorbed because of the molecular size of what’s inside the capsule that’s the first thing to do the second thing is that when we’re carrying medicines across the skin we normally use agents that are known to facilitate absorption

And that’s not again going to be in a gel fill capsule so my general advice firstly for the first part of the question is don’t prick open a capsule and expect it to work secondly even if you’ve got a topical tutasteride compounded our experience with finasteride suggests that if you were a patient who had used oral finasteride got side effects and went to

Topical finasteride most of those patients would still get side effects yes because it still has to be absorbed it goes to the level some of it inevitably gets into the bloodstream so i’m going to presume without being able to give you a chapter in verse that the same is going to be true for deuterostoric yes but that’s still how it’s going to be effective

Because it has to be metabolized in order to uh and the active metabolite of that to to to have its effect so i would strongly discourage people to take things into their own hand and experiment with these things get it made up properly and then you’ll probably find it be more effective that way but also don’t think that topical therapy whether the finasteride

Digitastride gets you around the potential problem of side effects if you’re a person that’s going to react it still appears to happen um even with low-dose percentage topical finasteride injury testosterone good i think that’s good that answers those questions i hope you found that useful thanks very much for watching please remember to to like and subscribe

To the channel and we’ll see you on the next episode see you then take care

Transcribed from video
Q+A : Finasteride and Dutasteride By The Hair Loss Show