Hello, welcome to JustAnswer! I am a Veterinarian and will help you right away!So, your questions and your thoughts are wonderful. I can tell you have spent a lot of time with this, and have articulated your concerns very well.Firstly, I should say, that castration is the preferred treatment, and by far the most useful treatment in dogs that actually need treatment. Ben sounds like he was having secondary troubles like defecation difficulty (dyschezia) from the obstruction. This is definitely something we don't want him to suffer with, so treatment is necessary.It is important to know for sure that this was BPH (benign) and not something else like prostatitis from infection, or cancer. Typically that would require an ultrasound guided aspriate, and possible biopsy to be certain. Hopefully this was done?BPH prostate is usually very smooth and symmetrical growth on all lobes of the prostate. Not always, but malignant hyperplasia is often more painful and is usually more lobulated or lumpy. Blood in the urine can be associated with both.Osaterone acetate has been used as you describe. Another treatment which has been used, especially in dogs that are breeding dogs where castration is not desired is :Finesteride : " Finasteride blocks the action of 5 α-reductase, an enzyme that converts testosterone to dihydrotestosterone. Dihydrotestosterone is the biologically active hormone to promote prostatic hyperplasia in both people and dogs. Giving finasteride at 1 mg/kg/day, PO, for 16–21 wk, to laboratory Beagles resulted in a 50%–70% reduction in prostatic hypertrophy with no negative effect on semen quality. Lower doses of finasteride (0.1 mg/kg/day, PO, for 16 wk) reduced hypertrophied prostate volume by 43%, resolved clinical signs, reduced dihydrotestosterone concentration by 58%, maintained normal testosterone levels, and had no deleterious effect on semen quality, fertility, or libido in a group of nine dogs with prostatic hypertrophy. However, prostatic hypertrophy returns if finasteride administration is discontinued. The low dosage (0.1–0.5 mg/kg) of finasteride correlates to convenient dosing of one 5-mg capsule/day for dogs weighing 10–50 kg." -MerckKeep in mind that weight control is entirely up to you. We control the food. Most weight gain secdonary to castration can be mitigated by proper feeding. And most dogs do not change character at all. They are usually just less hyper and less likely to run away from home.I have heard of PEMF as well as ultrasonic bombardment of the prostate similar to lithotripsy in people that have kidney stones. I believe that most of these are part of canine models for human disease. So, they have been done, but have not been approved as a treatment for canines. It is more of a lab animal use for study of the comparative disease in humans.Here's a link to a scientific entry regarding ultrasound pulsing. Again, I am not aware of anyone doing this technique. But your best bet would be to contact the nearest Veterinary Teaching Hospital. That's where most cutting edge treatment would be done. ( click here for link to histiotripsy information)
Many thanks for your reply. Ben has not had an "ultrasound guided aspriate" so I shall arrange it and possibly a biopsy as well.
1a). Osaterone Acetate: Would you consider that this medicine is a legitimate, permanent option to castration?
1b). Do you consider that BPH could be contained by a week's dose of this medication, given about every 5 months, with the prostate's size monitored by assessing its size midway between doses of the medication -that being 2.5 months after the weekly course had finished?
2). Finesteride: Thank you for the information on this medication. Would you consider that it is legitimate to use this medication, on a permanent basis, in place of castration?
3). If you consider that the use either of the two medications noted above are legitimate options instead of castration which of the two do you consider to be the best option?
Note: I do not intend to breed from Ben but I am wary of an irreversible operation -castration- and I note that you think this would make him "less hyper" -but he enjoys being hyper and I like him being hyper too!
I am not sure if my reply to Dr. Ralston was received. It read as follows:-
Many thanks for your reply. Ben has not had an "ultrasound guided aspirate" so I shall arrange it and possibly a biopsy as well.
1a). Osaterone Acetate: Would you consider that this medicine is a legitimate permanent option to castration?
1b). Do you consider that BHP could be contained by a week's dose of this medication given about every 5 months, with the prostate's size monitored by assessing its size midway between doses of the medication -that being 2.5 months after the weekly course has finished?
3). If you consider that the use of the two medications noted above are legitimate options instead of castration which of the two do you consider to be the best option?
Osaterone was administered in test studies for one week, and compared to the regression rate after the same time period post castratio and found to be equivalent (roughly 60% reduction for both treatments after one week). Regression was measured about 6 months later (180 days) and enlargement had occured of the prostate. In some cases larger than previous before treatment.So, your question 1b) has no definitive answer. Giving the medication will likely lead to a reduction in prostate equal to castration. When the medication stops, (for either medications you have mentioned) the prostate will begin to become enlarged again. Monitoring will be needed on an individual basis for either medical treatment you use. In some cases, the medication may need to be given life long in order to keep the hyperplasia to a minimum and to reduce the clinical signs.So, monitoring at 2.5 months out may show enlargement or it might not. There is no definitive timeline that has been established. It sounds like a good model for experimentation, and you might even publish that! :) But, truthfully, my answer is we don't know.2) Finesteride of the two is likely my favorite because secondary signs were mostly reverseable (with both drugs) but not as likely to happen with finesteride vs. osaterone. And it should be noted we can't be sure of long term effects of administration.Finasteride specifically and totally inhibits 5-alpha-reductase. This enzyme is re sponsible for metabolizing testosterone to dihydrotestosterone (DHT) in the prostate, liver and skin. DHT is a potent androgen and is the primary hormone responsible for the development of the prostateKeep in mind that for either drug or surgical castration you will be altering the natural hormonal balance of Ben. With castration, you are decreasing testosterone by removing the testicles. With osaterone you are using progesterone like hormones (feminine hormones) to alter your pet. This can lead to feminization signs like breast tissue enlargement, et al listed above). Finasteride again is less likely to cause these signs. One study done in dogs reported no adverse effects or irreversibility of effects after treating for 21 weeks at 1 mg/kgAND, it is important to note that all of these studies have been used to treat EARLY stages of BPH. Later stages, it may no longer be effective. So, for long term treatment, we just don't know. Treatment might not be effective on sequential treatments. Castration however is a one time treatment with possible permanent solutions with a well established history of side effects and outcomes (maybe 100's of years of scientific evidence, and maybe thousands of human experience with castration of animals) versus newer hormonal treatment which isn't fully established and we don't know what all the long term side effects would be.So, that is my best opinion after review of the available data.Given only three options and having to chose for my own pet, by far I would chose castration as the best option. Followed by finasteride, and lastly osaterone.Treating for a week, and then checking for regression at 2.5 months is also not likely to be an effective method either. Likely either medication will prove more effective at a once daily dose continuously in order to be effective.Given once daily, both medications do appear to be legitamite choices for treatment of BPH. It remains to be seen if they are effective permanent solutions.