With the suspension of Cincinnati Reds pitcher Edinson Volquez for performance enhancing drug use and a swirl of rumors that the agent involved was clomiphene (also known as Clomid,) I thought it timely to write about how clomiphene works and how it’s used. From what I read on the internets, there is an enormous amount of misinformation floating around out there.
To understand how clomiphene works, you need to know how the pituitary controls the making of testosterone in the testis. Testosterone is made by Leydig cells in the testis, which I explained in my last post. The pituitary releases a hormone called luteinizing hormone (“LH”) that stimulates the Leydig cells to make testosterone. Testosterone is converted to the female hormone estrogen, (which I also explained in my last post,) and estrogen tells the pituitary to stop making more LH. This kind of negative feedback system is common when it comes to how hormones work. It’s just like a thermostat and heater. As the room gets warmer, the thermostat sends less electricity to the heater. When the room gets colder, the thermostat sends more electricity to the heater.
Clomiphene works by blocking estrogen at the pituitary. The pituitary sees less estrogen, and makes more LH. More LH means that the Leydig cells in the testis make more testosterone.
As I explained in my last post, giving testosterone to a man does just the opposite. The pituitary thinks that the testis is making plenty of testosterone, and LH falls. As a result, the testis stops making testosterone, and the usually high levels of testosterone in the testis fall to the lower level in the blood.
So clomiphene is a way to increase testosterone in the blood and the testis at the same time. It preserves testis size and function while increasing blood testosterone.
Unfortunately, clomiphene is not FDA approved for use in the male. Like most of the medications that we use to treat male fertility, the pharmaceutical company that originally sought approval by the FDA did it for women. Clomiphene is now generic, and it’s unlikely that anyone will pony up the hundreds of millions of dollars necessary to get it approved for the male. That’s the bad news. The good news is that it means that this medication is fairly inexpensive, cheaper than most forms of prescription testosterone. Can a doctor prescribe clomiphene for a man? Yes. It’s “off label”, meaning that it’s not FDA approved for use in men.
As a medication, clomiphene is usually well tolerated by men. In my experience, most patients don’t feel anything as their testosterone rises. Those that do feel an increase in energy, sex drive, and muscle mass, especially if they work out. Very rarely I’ve had patients report that they feel too aggressive, or too angry. Very very rarely (twice in the last 20 years) I’ve had patients report visual changes. That’s worrisome, as the pituitary is near the optic nerve in the brain, and visual changes suggests that the pituitary may be changing in size. Because the skull is a closed space, it’s alarming if anything in the brain changes in size. In the last twenty years, I’ve also had two patients who had breast enlargement (called “gynecomastia”) while using clomiphene. Needless to say, for any of these problematic side effects, the clomiphene is discontinued.
So that’s the story with clomiphene. It can be used in the male, either for fertility or low testosterone levels. It’s an off label prescription drug. It works, and is usually well tolerated by men who take it.
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Hello sir, I was curious if any of your patients treated with clomid had ever suffered from testicular cancer or cataracts.
Some sources say that clomid is carcinogenic, do you believe there is any truth to that?
Thanks in advance.
I don’t believe that clomiphene citrate is, as a molecule, carcinogenic. If a tumor is stimulated by testosterone, (what we call “androgen responsive”,) then the effects of clomiphene–increasing testosterone–may serve to stimulate the tumor. That’s why it is important for a man treated with the medication to see a doctor regularly.
Doc,
If clomid raises your test then it should also raise your estrogen; what is the point of that when trying to stabilize the hormonal level? Also wouldnt arimidex do the exact same thing except do so by also lowering estrogen? Can they be used together?
thanks
Evidence suggests that a ratio of testosterone to estradiol of over ten to one is consistent with a good working sperm factory. So if the estradiol rises but remains less than that ratio, it is likely not a problem. Anastrozole does not do the same thing: you might want to read my blog posts on how each works.
I am currently 40 years old. About 10 years ago I was experiencing depression and anxiety symptoms. My therapist put me on Paxil which I was on for 4 years. Then accidentally I came upon the fact that my testosterone levels were abnormally low. My old endocrinologist put me on testosterone replacement therapy which I did for 2 years until I realized that it was making me infertile. I went off of the testosterone replacement therapy and my new endocrinologist about 2 years ago put me on Chlomid. The chlomid miraculously keeps my mood strong and I feel normal. I was recently married and was able to empregnate my wife within 2 months of marriage. Unfortunately, we just had a miscarriage after 10 weeks. Whenever I have tried to stop using chlomid my mood got lower and I my anxiety level went up so I would quickly return to it. It seems like I will be spending the rest of my life on chlomid. I take 1/2 a pill (25mg) every other day. Are there any side effects associated with long term chlomid use? Should I do an ultra sound of my testes every couple of years to make sure they’re ok? Its hard to believe that there is a therapy like this without sideeffects.
I’m sorry, Vik, but I can’t answer personal questions about your health. Please read the FAQ.
Thanks for putting together such an informative blog! I was just wondering how clomid compared to androgel as a form of treatment in secondary hypogonadism (ie. what testosterone levels might be expected) ? Also, is clomid used by itself or in conjunction with other drugs? And how might it compare to drugs like HCG or HMG? Also, would nolvadex be as effective as clomid? sorry for so many questions and thanks for any input you can provide.
HI James, I’ve answered a number of questions like those before, including the one on tamoxifen. I know that the comments aren’t as easy to search as the rest of the blog, but you might want to scan back through them. 🙂
Doc,
Do you know anything about using Chlomid as a treatment for existing gynecomastia? Or any other selective estrogen receptor modulators?
It is a problem that effects an incredible amount of men.
Thank you.
It doesn’t make sense to me: if anything, clomiphene may increase estradiol levels.
Hello , My name is Christopher i’m 29 yrs old and my wife and i had been TTC for over a year before we decided that it was time for me to go get checked out.. so i had a SA done and my count was like 600k per ml but i had good volume so i went to see a uro dr and my labs came back as follow FSH : 20.2 , LH 8.5, PROLACTIN 17.9S, TESTOSTERONE 156 after which a was giving and ultrasound of my testes to check for varicocele and that checked out normal due to my labs #’s being like they were my dr suggested me to an endocrinologist to have my levels evaluated and my MRI brain w and w/o gadolinium came back normal so my uro dr prescribed me Clomiphene 50mg taken once daily .. so my question to you is with me taking this med what kind of results should i see when i go back for another SA in 3 months? is their anything else that i can take that could help me with my sprem count? will taking this med also help to correct my abnormal labs? thank you for your time dr. and please excuse my grammar and spelling for i am not the best when it comes to typing.
I’m sorry, Christopher, but I can’t answer personal questions about your own health. Please read the FAQ.
Ok, thank you for your time.
Very confused about the conflicting studies on sleep apnea and testosterone levels; i.e. sleep apnea causes low testosterone, testosterone therapy worsens sleep apnea, testosterone tx improves sleep apnea, etc.; what is your take on whether treated sleep apnea is a relative or absolute contraindication to testosterone replacement? In general, would you think clomid would be a better choice for patients with sleep apnea and low testosterone? Thanks!
The story of sleep apnea and therapy for low testosterone is very confusing. As worsening sleep apnea has been described with testosterone therapy, we generalize it to all forms of therapy for low testosterone, possibly incorrectly. It’s another example of where data would really help us. As to treating someone with pre-existing sleep apnea, it really depends on the individual patient. We don’t know if clomiphene is better or worse than testosterone for someone with sleep apnea (accepting that they can use testosterone–if they want to still have sperm production, that would be another story.)
This Blog is very informative.. I would greatly appreciate it if you could assist me in answering a few questions for me for my report on male infertility. if so my first question is How long after clomid treatment does it take to see a rise in testosterone? at what levels of testosterone should a man have to produce healthy sperm? whats the average length of time that a man must remain on clomid before it can make a postive impact on sperm? what’s keeping the FDA from recognizing clomid as a treatable treatment for male infertility?
Thanks! Testosterone rises very quickly, but sperm production is much slower. See my blog post on how long is the sperm factory 🙂
Thank you so much for the information Dr..
Hello again sir, I would like to know if you have seen any type liver dysfunction associated with clomid use over the years.
Thanks in adavnce.
I haven’t in my own patients, but that doesn’t mean that it doesn’t happen: some of my colleagues have reported it. It’s yet another reason why a guy who is taking clomiphene should be doing so under close medical care.
Doc,
Do you think there is any chance to have kid with Kleinfelter Syndrom (27-Chromoson) – With no Sperm?
Thanks.
Sorry, Ron, I don’t quite understand that question.
Doc,
Do you think Clomid will Increse the Risk to Vision, if you have High Prescription for Eyes with History of Retina Detachment and Glacoma in the family?
Thanks.
I think that person with such a specific history of eye problems considering clomiphene should really see a doctor 🙂
If Clomid is not typically prescribed for men, how would you suggest asking our doctors for the prescription? I have mentioned it before to my TRT doc and he says he has never heard of its use in men to help with low test and low libido/ED issues.
Thanks,
M
Hi Mark, the FAQ has some suggestions on how to find doctors that are familiar with male reproductive endocrine therapies.
It worked out for me today. My doctor gave me a prescription of clomid when I simply asked him for it. He had never personally prescribed it so he is also interested in how it works for me.
I’m 32 and have low T. Went to primary care doc and he put me on testosterone therapy but once he realized I still wanted to have kids he discontinued. Referred me to a urologist and now I am on clomid. Been on it for about 6 weeks and levels were back up to 600s at last check up last week. I have been experiencing severe mood swings an bouts of depression…is this a common side effect and will this eventually get better?
I’m sorry, Brad, but I can’t answer personal questions about your own health. Please read the FAQ.
I am a Family Doctor looking to help my low T patients and have been prescribing Clomid for a few years now. I follow improved patient symptoms, T-levels, PSA and exam, annual eye exam. I have about 20 patients on Clomid and none have had adverse effects. Most are on 25 mg 3 X / week and this keeps there T in mid to upper range of normal after 3 months of therapy. Any thoughts on what might be the lowest possible dose and frequency of clomid to achieve good therapeutic results?
Thanks for this blog!
That’s a great question. In my own practice, the lowest dose I’ve prescribed was 12.5 mg twice a week. As you’re discovering, although most men seem to respond to 25 mg daily or 50 mg every other day, responses can be highly individual. Great to hear from you!
Hey Doc, I have read that since sidee effects with Clomiphene are fairly rare, athletes have been known to take dosages as high as 1500mg per day. This is not a typo, I read it in the 1996 Anaboolic Review. I understand most men use Clomiphone for 2 weeks (100mg/day for week 1 and 50mg/day for week 2) but was wondering how absurd you think dosages in say the 200mg/day, 400mg+/day would work over an extended period of time. I don’t believe that more is better with regard to 99% of most situations out there in the world but am curious what you think on this one. Let’s say someone even went to the trouble of taking silymariin or milk thistle to support healthy liver function while taking higher dosages of Clomiphene for an extended period of time. What would it mean if your opinion if a man taking a dosage of say 400mg/day of Clomiphene saw sex drive and ability to get an erection or ejaculate go down very significantly. It spells elevated estrogen levels to testosterone levels in my opinion but wanted to know your thoughts on that. Thanks!
I’d say that man should really be under a doctors care, and that “supporting liver function” by those measures is highly speculative.
Can you list some possible side effects that may take place with an intake of Clomiphene exceeding the 25mg-50mg every other day I saw you suggest in an earlier response you gave to someone?
Hi Jim, in this post I detail the side effects.
I am 21 and used prohormones (bad mistake) and I have not been the same since. I got testosterone blood tests taken twice and it was somewhere between 400-500ng/dl.
I checked the average level of testosterone for my age group and it is 650+ng/dl. What are the chances of a doctor doing a ‘clomid restart’ therapy to see if I can get myself back to normal? Can only a urologist or endocrinologist prescribe Clomid? Thank you.
I’m sorry, Michael, but I can’t answer personal questions about your own health. Please read the FAQ.
Michael,
I would suggest making an appointment with a urologist and explain to him that you’ve taken pro hormones and would like professional medical help. He will likely order blood tests and then make the determination for clomid therapy.
I am 34 years old and I myself experimented with pro-hormones in my late 20s. I never felt the same after taking them. I had not taken anything since then. I have been on Clomid now for 6 months at 50mg every other day. After 6 weeks my Test levels rose from 305ng/dl to over 600. So the Clomid can work for you.
Hi Doc, sorry for all the questions and even moreso for coming back with more.
Could benefits similar to clomid be achieved by taking an aromatase inhibitor like exemestane or anastrozole instead of clomid?
Would the two combined have a synergistic effect?
Lowering estrogen levels has the same benefit as raising testosterone levels does it not? Is there a downside to decreasing your estrogen levels or estradiol levels?
Thanks!
Hi Jim, you might want to read some of my other blog posts. I discuss aromatase inhibitors in depth in another post.
Is clomid usually prescribed for short periods? Have you seen any reversal of hypogonadizm?
Clomiphene is not typically prescribed for short periods. If it’s used to treat low testosterone, then that’s usually a long term therapy. If it’s used to treat male fertility, you should read my post on the sperm factory for that time frame 🙂
First of all I am happy that I came across this website during my online search for information regarding clomid therapy.
I am 34 years old and have been on clomid for 6 months now prescribed by my urologist. My baseline T level was 305ng/dl. After 6 weeks on clomid at 50mg 3 days a week my levels rose to just over 600ng/dl. I had my 6 month bloodwork done two weeks ago and my levels had dropped to 450. I had not taken clomid for 3 days prior to this blood tests. I wanted to see the affects. Not what I was hoping for.
My doc then ordered me to take 50mg every day and then more blood work in 6 weeks. Followed by another 5 months on clomid for a total of a year on clomid therapy
My question is how long is “long-term” clomid therapy? Has there been any studies on long term side effects?
Thanks in advance for your reply!
JasonB
I’m sorry, JB, but I can’t answer personal questions about your own health. Please read the FAQ.
Hi Doc, in your experience working with patients what might it mean if a man’s sex drive went down after beginning treatment with Clomiphene? Is that a sign the dosage prescribed was too high? Does taking an aromatase inhibitor increase or decrease sex drive typically? Thanks for the information!
Jim
It’s an unusual response, but it can happen. LIke all unusual responses, there isn’t one explanation or one way of dealing with it. Any unusual response should be reported to the man’s doctor.
Doc, been stumbling around online, and found your thread. thanks for having some solid info amongst the confusion. i haven’t talked to my doctor about clomiphene for two reasons, she’s an old woman, and secondly because its the VA. i’m looking to boost my T and the size of the little guys, i know it sounds silly but i have had very stressful jobs for close more than five years running, and i know they’ve shrunk, my energy is way down, my sex drive isn’t even half of my wife’s and erections point right in front of my toes. : ( worst part? i’m 28i’ve found a website that sells the clomiphene, but offer 25, 50, and 100mg. which do you think would be good for me to start with? Thanks doc : )
I’m sorry, BenJamin, but I can’t answer personal questions about your own health. Please read the FAQ.
Thanks for all the time you put into this site- I think it is very informative. I’m premed and love endocrinology, so very fascinated and appreciative.
I know you discussed a minimum effective dosing of 12.5mg 2x week. I’m curious- have you noticed a direct dose-dependent effect, or is it more of a meeting a minimum threshold/ blood level and then minimal increase in response as the dose is increased type of situation?
Also, I understand why longterm therapy for low T is seemingly necessary, but have any of your patients gone off treatment to see if their system has rebooted? I was just thinking about antidepressants, and how receptors can downregulate, thus rebooting the system. Could something similar happen with hypopituitarism, or is that not likely? I guess that goes to the etiology of the disorder, which is a whole other matter.
Thanks again for your time!
Great questions, both. There is usually a dose-dependent effect, different for each patient, of clomiphene on serum testosterone concentration. Alteration of symptoms is of course less directly related. As for “rebooting”, my experience is anecdotal. It can happen, but not often. Good luck in your career!
Thought of one more question- In treating low T for a prolonged period, have you observed instances of previously successful treatment becoming less efficacious? If so, what then, and also what do you think is the underlying physiology behind such a phenomena?
Tachyphylaxis is uncommon, but it can occur. The mechanism is not fully elucidated.
If a man is on clomid and his wife becomes pregnant, is there a risk of defects with the baby.
There is always a chance of birth defects with any pregnancy. But there is no evidence that I know of that treating low testosterone with medication such as clomiphene increases the risk.
I am glad to know that there’s an online doctor who could give us some valuable information regarding male infertility cases. Five years ago, I have been examined to have a pituitary tumor that affect my vision slightly and a loss of sperm production.
Is there any chances to get back fertility if I would take clomid even without prescription? Please help me…God bless!
Thanks for the kind words, Joey, but I can’t answer personal questions about your own health. Please read the FAQ.
In addition doctor, I am taking Parlodel 2.5mg everyday to my pituitary tumor since I was diagnosed 5 years ago. It is alright if I will be taking clomid in order to restore my fertility and sperm production? Thanks again doctor…
Hello again, I would like to know what effect clomid therapy has a negative impact cholesterol levels.
Thanks in advance, sir.
Clomiphene therapy doesn’t directly change cholesterol levels, but the increase in testosterone might. Studies are conflicting on this possible effect. If he’s concerned about his cholesterol, a man should discuss it with his doctor.
Hi Doc,
Thanks for the great web-site!! three quick questions :
1. have you had any experience using hcg instead of clomid for secondary hypogonadism and what are your thoughts?
2. what is the best regimen for clomid in med with secondary hypogonadism (i.e 25 mg qod vs 50 mg qod vs 25 mg qd) and why?
3. do you find clomid to be as efficacious in young males wishing to maintain fertility with a diagnosis of secondary hypogonadism as testosterone replacement with regard to improving libido, improving fatigue and mood?
1. Great question! See my most recent post. 2. It depends on the man’s individual response to medication as determined by his doctor. 3. Response to any form of increasing testosterone is individual, and depends on the man. If a man wants to preserve his fertility, he shouldn’t use testosterone directly, as I explained in this post.
Woops, didn’t type that out too well there.
Let me type that again.
Does clomid therapy has a negative impact on cholesterol levels?
Hello online Doc, is it alright to take clomid without the knowledge of my doctor? Thanks
Hopefully by “online Doc” you mean doctor that is writing a blog and not someone doing doctoring online, because I’m the former and definitely not the latter 🙂 I strongly recommend taking clomiphene only under direct supervision of a physician, both to insure that it is achieving the desired effect and that it is not causing harm to a man’s body.
Do you have any experience with men using Clomid for chronic hypogonadism over the long term? Is this typically considered a safe therapy for a man to use for life (at a low dose)? Are there any possible long term side effects?
Hi Chris, surf through my other posts and the over 360 comments on this one, and you’ll find that I’ve answered those questions a few times 🙂
If a man takes 25mg of clomid per day, how many days would it take for the increase in testerone to show in a blood test.
Hi Abdi, surf through my other posts and the over 360 comments on this one, and you’ll find that I’ve answered that question, too 🙂
1. If you found that clomid use lowered IGF-1 significantly in your patients would you be concerned if the IGF-1 was still in the normal range?
2. If clomid did not raise testosterone enough in a patient can you give an example of another therapy that would raise testosterone and maintain fertility?
Hi Scott, there’s so many hypotheticals in the first one that I really can’t answer it. For the second, surf through the rest of my posts, and you’ll find a number of answers to that question 🙂
Hi Doctor.Have you ever heard of HDEA having a negative feed back on the HPTA? Will HCG cause negative feed backs?
You’ve got a few nonstandard acronyms making it difficult for me to understand what you’re asking.
Hi Doctor,
Thanks for the nice blog! Very imformational. Can too long abstinence (say one or 2 weeks) lower the quality of sperm?
Thanks!
Zuzu
Studies indicate that optimum abstinence is two to three days, no more or less.
Thanks, Doctor! Does that apply to all age groups, young and old? Thanks.
Zuzu
Yes.
Sorry I miss spelled that, would DHEA cause a negative feed back.
You mean does a supplement with androgenic properties such as dehydroepiandrosterone turn down luteinizing hormone production by the pituitary and as a result decrease the making of testosterone by the testis? Yes. See this study.
Thanks, that makes sense,im 30 yrs old, I took a pill called extenze one night and one of the ingredients was DHEA. When i woke up the next morning I noticed a dramatic decrease in my facial hair growth and things have just gone down hill from there, including a shrinking and softening of my left testicle. I cant see how these companies can get away with selling this stuff without a perscrition! I didnt think taking one pill could do this to me. I would tell anyone to stay away from these bogus pills!
Thanks for the great response to my last question about hcg.
Here is another question if you have time. Can you please discuss the use of aromatase inhibitors in men with low testosterone. why do you initiate? when do you initiate? Does this thereapy , in addition to testosterone replacement improve sx of low testosterone?
Thank you very much !
Hi Bob, you really should leave this particular post and read the others on my blog–you’ll find many of your answers in my other posts!
Hello Dr,
I’ve read several articles, and ran across a couple statements about Tagamet (cimetidine), sulfasalazine, or nitrofurantoin are used to treat ulcers, gastrointestinal problems, and urinary tract infections. These medications may impact sperm production and sperm count. Just want to know if taking Omeprazole 20 mg twice a day to treat gastritis will have any negative effect on sperm
That’s one to ask your doctor, Lucius!
Hey doc,
Would taking clomid help with getting an erection?
If a man has low testosterone, it may.
Hi doctor, I just had one more question about clomid and I will quit bugging you.
If a man naturally has normal or even high testosterone levels would taking clomid make his levels even higher?
Although thresholds are typically used to determine a “normal” testosterone, it varies from man to man. That’s why it’s so important for a man to see a doctor when being treated with clomiphene, so that the doctor can assess exactly what’s being treated.
Have people taken Clomid as an alternative to taking performance enhancing, anabolic steroids such as Testosterone? Are there any studies or anecdotes you can share? What would be the pitfalls to doing so. Thank you for your post!
As a physician who cares about the health of men, I would never advise clomiphene or any medicine for “enhancing performance”. This blog is about treating medical problems, including low testosterone, infertility, erectile dysfunction and other male related illnesses.
Hi Doc
You said in the post that most men don’t feel anything as their testosterone level rises.
If so, is there a point in taking Clomid for depression and anxiety caused by low testosterone?
Thanks
Most men with infertility as their primary symptom of low testosterone don’t feel other effects as their testosterone rises on medication. Men who have other symptoms of low testosterone are often treated by increasing the testosterone. If those symptoms don’t go away as the testosterone rises, then they’re probably not due to low testosterone.
I’ve heard clomid can cause acceleration of male-pattern baldness, acne, nipple sensitivity, and prostate growth. Have any of your patients experienced these side effects? If so, what percentage of patients and how severe?
I’ve listed the common (and not so common) side effects on this blog. Read a few of the other posts 🙂
Can you explain how clomid works for fertility issues in men? And what issues does it treat? Does this help with low count/motility? Can u suggest something that does?
Thank you.
April, you really need to read through the rest of this blog. I explain what you ask on other posts.
Doc,
So in theory, by taking Clomid, testosterone will rise, increasing muscle mass, and weight loss. Is this correct?
I wouldn’t recommend clomiphene purely for increasing muscle mass and weight loss if a man has a normal testosterone level already.
Hi doc:
What if a man takes clomid and proviron with no aparent effect on his libido BUT when he introduces Nolvadex it all works out well ( nice libido , hard erections) . Can we say that he most likely be too sensible to estrogen ( or present high levels of this hormone)?
Regards
Please read the FAQ regarding mixing drugs.
I wanted to know if there are any drugs for males that you have noted in your personal expereince (or that you are aware of), that as a side affect cause excessive hair growth on the body, such as clomid, danazol, etc. I also wanted to know if men use danazol(danocrine) to increase testosterone. Thanks Doc.
Excessive hair growth is not a common side effect of the medications used to stimulate the pituitary in men. Danocrine is not typically prescribed for the male.
Thanks Doc, this is a very helpful website, i started taking Clomid soon as i found this page, i was diagnosed azoospermia, the doctors in my country could not tell me why it was so, through my search on the internet i chanced on your website.
though i have not done another test yet, I can see my semen texture has improved, i am currently taking Clomid with Vitamen E, Zeeman and Vitamin A.
My question is, How long can a person take Clomid to see results?, i take 50mg every night and what other drug works best with Clomid.
Hi Kojo, unfortunately I can’t provide personal care via this blog. Please read the FAQ. You should ask the doctor who prescribed it these questions.
Dear Dr. Niederberger,
You’re a beacon of light shining in the darkness! Many thanks for all the help you have generously provided thru this informative blog! Question: In males with Low T who respond well to treatment with Clomiphene Citrate, can you speculate on the etiology of the disorder? It would seem that the disorder typically develops during middle age or later in life, and I wonder if causation is genetic or environmental, or perhaps some other trigger. If environmental, what is the most practical way of attempting to determine the offending agent? Thank you in advance for your thoughts. Scott
Good question, Scott. Men of all ages after puberty can have low testosterone. For young men, it is likely due to how their pituitary developed. For older men, evidence suggests that the hypothalamus, pituitary and testis all get sluggish as many parts of the body due when they age.