Updated: Sep 29, 2022
I am not a doctor. This is just what I have gathered trying to help me understand my disease and my treatment options. Your doctor knows infinitely more about your body, your disease and your treatment than I do. Always ask your doctor about anything you read here if it interests you.
Reason for hormone therapy
Prostate cancer uses the male sex hormones to grow. The main male sex hormone is called testosterone. Here I will use "Testosterone" to stand for ALL the male sex hormones.
How hormone therapy works
Hormone therapy works either by preventing the production of testosterone, or by stopping the prostate cancer from using it.
When hormone therapy is used
It is mostly used if your prostate cancer has been found to be outside your prostate (by scans), or thought to be outside the prostate (by blood tests like PSA).
It is also used with radiotherapy (radiation) because it makes radiation work better.
The regular injections - given every 1, 2, 3, or 6 months
For radiation treatment hormone therapy is used - sometimes before or during radiation, very often afterwards. Your doctor will set the length afterwards by the aggressiveness of your cancer - from 4 to 36 months, 4 months or 18-24 months being most common.
For advanced prostate cancer patients the treatment is often used for life, often with other treatments added in the later stages.
The injections are expensive. In Australia the government pays (on the PBS).
Options for people in poor countries are further down this page - surgical removal of the testicles (orchiectomy or castration) and early hormone therapy tablets.
Common regular injections - Brand (chemical name)
Zoladex (Goserelin), Lupron (leuprorelin), Eligard (leuprolide), Lucrin (leuprorelin acetate), Suprefact/Suprecor (buserelin), Synarel (nafarelin), histrelin (Supprelin), Suprelorin/Ovuplant (deslorelin), Triptorelin (diphereline), Firmagon (degarelix)
Many of these require specialised preparations before they are administered, and special rules of administration. Not the sort of thing you could pick up from the pharmacy and do it yourself at home.
What all regular injections do
They all keep your testosterone low to keep your prostate cancer from growing.
All the regular injections (except for Firmagon (degarelix)) initially cause your testosterone to rise for a week or two before bringing it to the very low levels needed by the end of four weeks.
That rise in testosterone (flare), gives your prostate cancer a temporary growth that can cause an increase in symptoms for that time, particularly pain.
One solution for doctors is to inject a starter dose of Firmagon (degarelix) to begin with. Firmagon brings your testosterone down within a day or two. For injection number two (28 days later) and onwards they will give you whatever regular injection that has been chosen.
Another solution is to use one of the early hormone therapy tablets (see below) for a period of weeks before the injections begin in the hope that this will minimise flare. The decision to do this is not simple because it means the doctor can't be sure your testosterone is as low as it needs to be until a month after you begin the injections. Your Doctor may feel it is best to go straight on the injections and definitely get rid of the testosterone by the end of that first month.
Two regular injections are different from the others
Firmagon (degarelix) differs from all the others because it will immediately bring your testosterone levels down within days, with no flare, and keep it low. So, it is often used as a first injection dose.
Firmagon has also been shown to be better for men who have had cardiovascular problems – problems with their heart and circulation - heart attacks, hardened arteries, deep vein thrombosis etc. That benefit has been shown by high-quality research.
Not with research, but looking at what Firmagon does in your blood suggests to some doctors it maybe better for your heart and protecting your bones from prostate cancer for all men.
The biggest thing Firmagon has going against it is that it has to be taken every 28 days (4 weeks) - a timetable that location or personal life issues make it very hard for some men. It also means that the injection site pain has to be put up with for a few days every 4 weeks.
Triptorelin (diphereline) lasts longer in your body than some of the other hormone therapies, so it is good to prevent break-out (see below).
Triptorelin (diphereline) and Firmagon (degarelix) both keep the testosterone lower than some other hormone therapies.
Breakout of testosterone levels
These hormones therapies mostly work by having a pellet injected under your skin in your muscles or subcutaneous fat. In some the pellet is pre-prepared and looks like a grain of rice. And others the doctor will mix two components in front of you – much like you would at home with a two-part epoxy you buy from the hardware. Your doctor injects some mixture while it is liquid and it goes hard inside you. It is designed to slowly dissolve giving you the necessary dose as it does.
All our bodies are different and one man's body may gobble up the goodies before the anointed time. This leads to testosterone levels to get above your target (whether that is 50 or 20). This is called a breakout.
Another cause of breakouts is the injection timetable not being followed. If a man's shot is not on time, but 4 or more days late, about half the testosterone levels are more than 20, while about a quarter are above 50. The timetable is exact multiples of 28 days. Thinking of your spacing as 28 days or 84 days - rather than 1 month of 3 months. Repeated breakouts will mean you will likely need your next treatment to be added to hormone therapy sooner, and you your life won't be quite so long.
How low should your testosterone be?
Originally, testosterone testing was only accurate down to 50*, so this was set as the standard to aim for. Modern testing can accurately measure much lower levels. Research based on this modern testing shows that men who keep their testosterone level below 32 take longer before they need extra treatments, and live longer. Another looked at how long before hormone therapy was not enough, that is before the men became 'castrate resistant' and needed the next treatment to be added. When testosterone was kept below 20 that was 8.8 years, between 20 and 50 it was 7.5 years, above 50 it was it was 6 years. Firmagon brings the testosterone to 20 at 1 month, to 13 at 12 months. Triptorelin brings the testosterone to less than 10. A reminder here that I am not a doctor, so when I say that Firmagon and Triptorelin can better reach and keep to this low standard, your doctor may know other hormone therapy injections which also meet it. (For instance, though it takes longer to bring the testosterone levels low, after 9 months or hormone therapy Eligard (leuprolide) brings testosterone levels down to less than 10 in almost the same percentage of men as Triptorelin does.)
Short-term side effects of hormone therapy
If you have a short period of hormone therapy, say 4–6 months, it is most likely that any side-effects will resolve themselves gradually after you stop.
Long-term side-effects of hormone therapy
If your hormone therapy is for 18 months or more, low testosterone, and the side-effects it causes are likely to stay with you. Between 6 and 18 months it's the luck of the draw.
When looking at a long list of possible side-effects for hormone therapy, you should bear in mind:
You are not going to get all side-effects on the list.
Almost all men who are on hormone therapy tolerate the side-effects that come with it. Very few give it up.
The major side-effect is to keep you alive and active longer.
Almost all of the side-effects of hormone therapy come from your body not having the testosterone it is used to having. Sad part about this is, just changing brands will not fix these low-testosterone problems. Other problems can sometimes be fixed by a change of brands.
That does not mean the low testosterone side-effects cannot be treated - ask your doctor if something becomes a big problem.
Ironically, the very most effective treatment for fatigue, depression and some other side-effects is exercise. It is when you most need exercise that you least feel like it. However, my experience was that pushing myself to do exercise when I felt down often really improved my outlook.
Some side-effects – hot flashes and fatigue - tend to fade with time. They did for me.
Some side-effects slowly increase with time. For me, in the last two or three years I have been finding it harder to remember some names and some words. I feel this is probably the result of continuous hormone therapy during the past 1years, and not just because I am in my 77th year. I think this because no other aspect of my mind or memory is significantly impaired, and many men on long term hormone therapy have shared with me that they have this same problem with names and words.
Hormone therapy can thin the bones, making them easier to break, but that does not have to happen. The greatest part of the attack on the bones comes in the first year or two of hormone therapy. You monitor your bone strength by a bone mineral density test (BMD or DEXA scan). Your doctor may order this test when you start hormone therapy. Your local doctor can do this - a good idea because they can also measure and monitor by blood test other bone-affecting things like vitamin D and calcium.
But you can protect your bones yourself with exercise. Doesn't have to be massive. Because of my disability, I am limited to no more than 30 minutes walking on a good day. But I try to do this every single day I can. After the first 6 years of hormone therapy, my bones were significantly stronger than those of the young reference (an 18-year-old male). A month ago one measure was just above that 18-year-old male strength, the other still much stronger than an 18-year-old.
The hardest side-effect for men and their partners to come to terms with if they were not prepared are those that affect sex. Your sex drive can slowly drop off, but then return if you are just on a short course of hormone therapy. If you're a long-term therapy the sex drive will not return. Pleasure you get in your "member" will remain. If you have a regular partner, you would be well advised to seek professional advice early on as a couple. (PCFA Free call: 1800 22 00 99 will help you to find that.)
A hormone therapy "holiday" or "vacation"
You might imagine that taking a break from your hormone therapy might make it easier on you. The simple fact is that most of your side-effects come from testosterone being low, and you most likely will not recover enough to make any difference. Against this, not only are you giving your cancer a chance to develop, but you will be interfering with hormone levels which will give you an increased risk of developing problems with your cardiovascular system, increasing the chance of a heart attack and stroke. So pausing your hormone is generally not a good idea. Some men, however, may be suffering side-effects so strong that it becomes necessary. Some doctors may pause hormone therapy for men whose cancer cannot be located in the hope that with testosterone restored the growing cancer may be more easily seen on scans and treated.
You can find more about intermittent hormone therapy here:
Surgical removal of the testicles (orchiectomy or castration) was the first way of lowering testosterone. It is still the main treatment in poorer countries. In more affluent countries it may be ordered for a man if the doctor feels the patient may not be capable of sticking to a regular regime - for instance, if he has dementia .
Low-testosterone side-effects are the same as for other hormone therapies.
A major disadvantage is that it is permanent and irreversible. Men on injections who are having great troubles with side-effects can pause or cease or change the type of hormone therapy. Castrate men are stuck with it.
The safety of orchiectomy, is something you will have to depend on the skill of your doctor to work out for you. The studies reported come down on both sides, and your doctor will need to look at the studies themselves, and look for weaknesses (like whether the study used an unbalanced comparison) to decide.
But, some studies do suggest that, especially for more advanced men, or for for older men, or for men with previous cardiovascular events, orchiectomy gives more major adverse cardiovascular and cerebrovascular events (things like heart attacks and strokes) that the injections.
The testosterone level after castration reached 20 in three-quarters of the men tested.
Early hormone therapy tablets
Casodex, Cosudex (bicalutamide), Nilandron, Anandron (nilutamide), Eulexin (flutamide), Avodart (dutasteride), Androcur (Cyproterone, a steroid)
These were widely used before injections are available, and are still important important in poorer parts of the world.
If your doctor feels it is worth the risk they may give a course a few weeks before your injections in the hope of avoiding flare (see above). Casodex, Cosudex (bicalutamide) is most often used for this purpose.
While Androcur (Cyproterone) is sometimes used for a short period for the same reason, it is also given in short periods for hot flashes. It is not available in some countries because long-term use actually aggravates prostate cancer.
Newest standard hormone therapy tablet
Orgovyx, Relumina (relugolix) is a tablet which functions in the same way as Firmagon. Its use was approved by the FDA (Food and Drug Administration) for the United States just one year ago. I have not included it here because it is not yet available in many countries, and may incur insurance and other problems in the USA.
Next step hormone therapy tablets
If your prostate cancer is so aggressive that the injection hormone therapy above is not enough, or may not be enough, to keep your testosterone low enough, other drugs and treatment will be added. I have noted some of them here because, technically, they are actually hormone therapy. They are not usually referred to in that way, and 'hormone therapy' usually is used to refer only to the injections above and the early hormone therapy tablets.
The next step tablets: Nubeqa (Darolutamide), Erlyand in Australia, Erleada in USA (Apalutamide), Xtandi (enzalutamide), Zytiga (abiraterone).
Despite my cognitive problem I reported above, I can still produce a reasonable looking document like this one, and publish it on this, my reasonable looking website. Don't be fooled! I am not a doctor. The information I have gathered has been for myself and a few mates in the same situation. My bias is clear. I started with Zoladex, and changed to Firmagon seven years ago. With Firmagon being in short supply a couple of times, I have Triptorelin in mind as a reserve. UPDATE: Changed to Triptorelin (diphereline) every 84 days because it holds testosterone longer (in case there is another break in supply). A few of the injections on the list above I know nothing whatsoever about.
On the other hand, your doctor, especially your specialist, more especially your medical oncologist, will know about all of these and may well know very good reasons for you to use them. Ask your doctor!
*Testosterone level targets referred to above
Historical: 50 ng/dL, From research: 32 ng/dL, Super-low: 20 ng/dL
Same levels in Australian units
Historical: 1.73 nmol/L , From research: 1.1 nmol/L, Super-low: 0.69 nmol/L