Finasteride's Effect on Scalp DHT Levels

[Carlos Marcello]

Hello everyone..

I want to learn the fact about finasteride's effect of scalp DHT..

I don't know which study is true.

In this study, 5 mg finasteride blocks scalp DHT by % 69.4.

http://www.ncbi.nlm.nih.gov/pubmed/10495374

But in this study 5 mg finasteride blocks scalp DHT by %41.

http://www.bernsteinmedical.com/reso...s-finasteride/

Which study is true ?

 

[xRedStaRx]

Neither.

 

[Ventures]

Neither.

So what percentage of scalp DHT is blocked by 0.2 mg of finasteride and doses above, according to you ? That does depend on certain genetic phenotype but in average it should be roughly 50 % ?

 

[xRedStaRx]

So what percentage of scalp DHT is blocked by 0.2 mg of finasteride and doses above, according to you ? That does depend on certain genetic phenotype but in average it should be roughly 50 % ?

Measurements of scalp DHT are not an accurate representation for finasteride effect, when compared cross studies.

I'd say that finasteride at 1-5 mg reduces follicular DHT by around 50%.

With 50 mg reducing follicular DHT at a plateau of 90%.

 

[Ventures]

Follicular DHT consists mostly of type II DHT which is blocked by finasteride. You mentioned earlier that finasteride doses 0.2mg finasteride and above provide enough finasteride molecules to block all 5ard-II enzymes in average male. And this 50% of follicular DHT which is left after administration of finasteride is result of 5ard-I enzymes which haven't been blocked or ?

So it is DHT type II which is most dangerous to scalp hair, right ? And this DHT-type II is generated locally in Dermal papilla cells inside hair follicles.

 

[xRedStaRx]

Follicular DHT consists mostly of type II DHT which is blocked by finasteride. You mentioned earlier that finasteride doses 0.2mg finasteride and above provide enough finasteride molecules to block all 5ard-II enzymes in average male. And this 50% of follicular DHT which is left after administration of finasteride is result of 5ard-I enzymes which haven't been blocked or ?

So it is DHT type II which is most dangerous to scalp hair, right ? And this DHT-type II is generated locally in Dermal papilla cells inside hair follicles.

Yes, but in reality, that doesn't quite happen as much as we would like. The amount of 5-AR II enzymes in our body can be effectively inhibited with only 0.2 mg of finasteride, but we are assuming a vitro experiment in this case. In reality, there are variable IC50s for different tissue. For example, around 1 mg of finasteride is enough to block all of 5-AR II enzymes on the prostate and liver, but does less so for the scalp and hair follicles. So you need a much higher concentration of plasma finasteride to achieve the same levels of exposure, or inhibition, for scalp tissue against the prostate or liver. This is why a small dose of finasteride reduces serum DHT by a lot, because it works better on the larger organs, but doesn't have that much effect equally for all peripheral tissue.

It's estimated that around 50 mg of finasteride would have 85-90% of intrafollicular DHT reduction, compared to the 30-60% of the lower doses. I'm using wide ranges because pinpointing accurate values would be futile. The reason why Dutasteride works better than finasteride is because it has an even higher affinity towards 5-AR II enzymes, so you can effectively use much lower doses to get the same effect, or the same ones for a better effect. The plateau inhibition levels of 5-AR II for finasteride vs dutasteride was around 85-90% vs 96-99% for recommended doses. But needs much higher doses to get that level on inhibition for scalp tissue and inner root sheath.

 

[Ventures]

But the goal is to find the optimal dose which reduces follicular DHT and in the same time doesn't cause striking reduction of plasma DHT and DHT levels in other tissues, like brain, pennis, chest. DHT is primarily locally generated and metabolised which means, if you reduce significantly its levels in some tissues, like chest, you could experience negative side effects as development of breast enlargement/gyno since it shifts DHT/E level in favor of Estrogen.

10 mg of finasteride is strong and high dose, but maybe it doesn't result in much more decrease of intrafollicular DHT than compared to doses such as 1.25 or 5 mg finasteride. So in turn you could have same effect on hair but greater sides as gyno, loss of libido.

Would you prefer to use 0.25 doses of finasteride in different time intervals, for example swallow 0.25 mg in morning, and 0.25 mg in evening or night in the same day ? What I mean, finasteride has pretty low half life time, so it would be smarter to use it in different intervals.

 

[xRedStaRx]

But the goal is to find the optimal dose which reduces follicular DHT and in the same time doesn't cause striking reduction of plasma DHT and DHT levels in other tissues, like brain, pennis, chest. DHT is primarily locally generated and metabolised which means, if you reduce significantly its levels in some tissues, like chest, you could experience negative side effects as development of breast enlargement/gyno since it shifts DHT/E level in favor of Estrogen.

10 mg of finasteride is strong and high dose, but maybe it doesn't result in much more decrease of intrafollicular DHT than compared to doses such as 1.25 or 5 mg finasteride. So in turn you could have same effect on hair but greater sides as gyno, loss of libido.

Would you prefer to use 0.25 doses of finasteride in different time intervals, for example swallow 0.25 mg in morning, and 0.25 mg in evening or night in the same day ? What I mean, finasteride has pretty low half life time, so it would be smarter to use it in different intervals.

If you want to up the dose, I'd just take it all at the same time instead. I believe raising the plasma levels of finasteride in one shot is more effective than a lower peak, but a more steady state level of the chemical.

Of course I do not really have much scientific information to back this up, but the theory being that the IC50 for the scalp and follicle region is more effectively reached at higher peak levels than lower but sustainable ones. Adding to the fact that finasteride is a suicide inhibitor of 5-AR enzymes, so a steady state concentrations are not decisive using that logic (or at least less important).

 

[Carlos Marcello]

Yes, but in reality, that doesn't quite happen as much as we would like. The amount of 5-AR II enzymes in our body can be effectively inhibited with only 0.2 mg of finasteride, but we are assuming a vitro experiment in this case. In reality, there are variable IC50s for different tissue. For example, around 1 mg of finasteride is enough to block all of 5-AR II enzymes on the prostate and liver, but does less so for the scalp and hair follicles. So you need a much higher concentration of plasma finasteride to achieve the same levels of exposure, or inhibition, for scalp tissue against the prostate or liver. This is why a small dose of finasteride reduces serum DHT by a lot, because it works better on the larger organs, but doesn't have that much effect equally for all peripheral tissue.

It's estimated that around 50 mg of finasteride would have 85-90% of intrafollicular DHT reduction, compared to the 30-60% of the lower doses. I'm using wide ranges because pinpointing accurate values would be futile. The reason why Dutasteride works better than finasteride is because it has an even higher affinity towards 5-AR II enzymes, so you can effectively use much lower doses to get the same effect, or the same ones for a better effect. The plateau inhibition levels of 5-AR II for finasteride vs dutasteride was around 85-90% vs 96-99% for recommended doses. But needs much higher doses to get that level on inhibition for scalp tissue and inner root sheath.

Thank you for this nice information.

I want to ask question about intrafollicular DHT reduction.

What's the effect of finasteride plus dutasteride therapy on ıntrafollicular DHT reduction ?

If I use 5 mg finasteride daily and 1,0 mg dutasteride/ weekly, how much intrafollicular DHT reduce ?

My target is % 90 intrafollicular DHT reduction..Can I do this with finasteride plus dutasteride therapy ?

 

[xRedStaRx]

Thank you for this nice information.

I want to ask question about intrafollicular DHT reduction.

What's the effect of finasteride plus dutasteride therapy on ıntrafollicular DHT reduction ?

If I use 5 mg finasteride daily and 1,0 mg dutasteride/ weekly, how much intrafollicular DHT reduce ?

My target is % 90 intrafollicular DHT reduction..Can I do this with finasteride plus dutasteride therapy ?

I do not see a reason to use finasteride alongside dutasteride.

Simply anything above and including 0.1mg of dutasteride would render finasteride useless when steady state concentrations are reached. Dutasteride is a more powerful inhibitor of 5-AR II enzymes, and that small dose is enough to equal finasteride's potency near it's plateau.

 

[Carlos Marcello]

I do not see a reason to use finasteride alongside dutasteride.

Simply anything above and including 0.1mg of dutasteride would render finasteride useless when steady state concentrations are reached. Dutasteride is a more powerful inhibitor of 5-AR II enzymes, and that small dose is enough to equal finasteride's potency near it's plateau.

Thank you for this nice answer..

I want to use finasteride with dutasteride together, because ı want to reduce intrafollicular dht by %90..

My target is 50 mg finasteride's on intrafollicular DHT effect..

5 mg finasteride/daily + 1,0 mg dutasteride / weekly = 50 mg finasteride / daily

for follicular DHT ??

 

[xRedStaRx]

Thank you for this nice answer..

I want to use finasteride with dutasteride together, because ı want to reduce intrafollicular dht by %90..

My target is 50 mg finasteride's on intrafollicular DHT effect..

5 mg finasteride/daily + 1,0 mg dutasteride / weekly = 50 mg finasteride / daily

for follicular DHT ??

If you want to use finasteride and dutasteride together for a more potent effect, then you can just use dutasteride alone because finasteride does not have an additive effect on dutasteride.

Again, anything above and including 0.1 mg of dutasteride / day will cross the barrier of finasteride at 5 mg, so taking finasteride at those doses would be a waste.

 

[Carlos Marcello]

If you want to use finasteride and dutasteride together for a more potent effect, then you can just use dutasteride alone because finasteride does not have an additive effect on dutasteride.

Again, anything above and including 0.1 mg of dutasteride / day will cross the barrier of finasteride at 5 mg, so taking finasteride at those doses would be a waste.

Thank you very much.

How much intrafollicular DHT reduced by 0,5 mg duasteride/ daily ?

I am asking this question because I read this combine therapy study:

http://www.gourmetstylewellness.com/interac...e-Dutasteride-Treatment-Androgenetic-Alopecia

Maybe finasteride plus dutasteride have more potent on intrafollicular DHT levels for some people..

 

[xRedStaRx]

Thank you very much.

How much intrafollicular DHT reduced by 0,5 mg duasteride/ daily ?

I am asking this question because I read this combine therapy study:

http://www.gourmetstylewellness.com/interac...e-Dutasteride-Treatment-Androgenetic-Alopecia

Maybe finasteride plus dutasteride have more potent on intrafollicular DHT levels for some people..

It does not.

0.5 mg of dutasteride probably inhibits in excess of 70% of intrafollicular DHT. Which should be more than enough.

 

[Carlos Marcello]

It does not.

0.5 mg of dutasteride probably inhibits in excess of 70% of intrafollicular DHT. Which should be more than enough.

I'm sorry but I'm confused.

Because in some studies :

0,5 mg dutasteride blocks scalp DHT by % 54

2,5 mg dutasteride blocks scalp DHT by %79

İs Scalp DHT equal to introfollicular DHT ??

 

[Ventures]

SCALP DHT = FOLLICULAR DHT(5-ard-II) + DHT inside SEBACEOUS GLANDS(5-ard-I)

 

[xRedStaRx]

I'm sorry but I'm confused.

Because in some studies :

0,5 mg dutasteride blocks scalp DHT by % 54

2,5 mg dutasteride blocks scalp DHT by %79

İs Scalp DHT equal to introfollicular DHT ??

No, scalp DHT will always be higher than follicle DHT, because these drugs mainly work on 5-AR II.

 

[Carlos Marcello]

No, scalp DHT will always be higher than follicle DHT, because these drugs mainly work on 5-AR II.

Thank you..

I understood you.

I am wondering answer of 2 questions :

1-) İs intrafollicular DHT important than scalp DHT ?

2-) When we think hair growth and side effects, sperm count etc, what must I use ? Finasteride 5,0 mg or Dutasteride 0,5 mg ?

I am waiting your answer..

 

[xRedStaRx]

Thank you..

I understood you.

I am wondering answer of 2 questions :

1-) İs intrafollicular DHT important than scalp DHT ?

2-) When we think hair growth and side effects, sperm count etc, what must I use ? Finasteride 5,0 mg or Dutasteride 0,5 mg ?

I am waiting your answer..

1) DHT other than follicular DHT is insignificant.

2) I'd say there isn't much difference between finasteride at high doses and dutasteride. I'd go with finasteride definitely. Less odds of side effects, and not much difference for hair.

 

[SciGuy29]

I actually want to bump this thread because after researching intensely, I did not find such good information anywhere.

The idea that Finasteride effects DHT conversion in different tissues DIFFERENTLY is a key point here.

For the last 4 months, I have been doing 1.25 mg of Finasteride every other day because I kept seeing that famous graph of DHT suppression after 1 mg and 5 mg dosage. I figured that taking it every other day would reduce sides and save some money with the same effect... NOT realizing that the graph was showing plasma DHT levels and not scalp levels.

I will definitely take it every day from now on... but I do want to find some of the studies that were mentioned... mainly on IC50 variances in different tissues and some of the inconsistencies of studies.

Edit: Edited font to be blue so that people see this and don't respond to the 2014 original post.