Questions and answers on a discussion about Delvosterone from our old Delphi forum

Question My little girl had her 1st season in august & went into phantom straight after. I treated her homeopathically and seemed to solve her problems (milk production stopped, etc) then last week (when she would have been due to whelp (had she been mated) she went off her food, started crying, making beds etc. She would not eat more than a mouth full of food and was losing weight fast, so tonight I took her to my vet, who gave her a Delvosteron injection. Now I am worried sick about possible side affects (having checked it out on the net. Has anyone here used Delvosteron? and what are the benefits and side effects?? I tried to avoid giving her anything un natural but got so scared at her weight loss. I would be most grateful for any information and advice (as I really don't want to give her this if she has a bad phantom again).
one very worried mum. Cath

Answer  My oldest Girl had 2 injections of Delvasteron. It stopped her seasons but never stopped her phantoms, she was still having them. So I stopped the injections. But she had no side effects at all.  Paula

Answer One of my girls had 3 Injections. She had first season at 8 month and went down hill after that. Lost weight and lost interest in everything. After the injection she was fine and there where no side effects with my girl. She had last injection a year ago. She is now 4 and back to normal seasons no phantom's, and her weight is fine now. She eat's like a pig now.  Karola

Answer My six year old suffers really badly with phantoms. For the past three years we have given her the delvosteron injection on a fairly regular basis. I have no intention of breeding from her, yet I am very reluctant to have her spayed. Are there any long term problems with the injection that you are aware of, if so I would be very interested.  Lynda

Answer  Don't know the exact side effects of long term use, but both vets i have asked including the one that gave the injections to my bitch, both said they would not recommend continued use for more than 2 years. Paula

Answer  As far as a know there are no long term problems. As I said my bitch is fine it helped her at the time to be able to mature and get a proper eating pattern. She was not eating at all before the injection, I had to force feed her. Now she is fine and eats anything that's not nailed down. Karola

Answer  We have used Delvosteron for a number of years now. We had 3 dogs (one was an oldie) and 3 girls. They all live in the house with us and I was worried that there might be friction between the dogs when one of the girls had a season. We are very lucky to have had the same vet for the last 35 years. I trust him totally and in his opinion the injection is safe to use long term. We lost our 2 oldies and now have 2 boys and 2 girls. I have just stopped using Delvosteron because a season should not cause so much upset now. The longest any of ours have been on the 'jab' is four years and I personally feel that is quite long enough. We have never had any side effects. You can still detect hormonal changes such as lack of appetite for a few days or milk production. A friend of mine had a girl who had really terrible false pregnancies, her vet put her on Delvosteron which helped a lot. Her symptoms were a lot less severe, she stayed on it all her life and lived to be a very good age, with no apparent side effects. Shirley

Answer My vet told me the risk long term giving Delvosteron or other is that they CAN develops mammary tumours faster then normal.....He said a good check every 5 months or more does help to be fast when that should happen. Gonny

Question  I was wondering if this drug is used if it would cause problems in getting the bitch in whelp at a later date if you wanted to as it is stopping seasons, does anyone know please, just curious. Hazel

Answer I have polly Jabbed, and have done since she was 8, but I only jab her when she comes into season, (not how they recommend Delvosteron to be use)....Polly comes into season without fail every 12 months so gets one injection a year.... if I was doing what most vets wanted she would be jabbed every 5 months....I have known a fair few bitches who have been jabbed on a regular basis and have never been able to get into whelp....but others, after a clean season and mated on the next seem fine , tumours are said to come in later life but then they can appear on a un jabbed bitch as well.. here is a bit about Delvosteron,  have a read its interesting Jo

Delvosteron Data Sheet
Presentation A white, aqueous, sterile injectable suspension containing 100 mg/ml proligestone. Preservatives methylhydroxybenzoate 1 mg/ml and propylhydroxybenzoate 0.12 mg/ml.
Uses The safety of progestagens is related to their molecular structure. Proligestone has a unique molecular configuration which makes it possible to administer Delvosteron at any stage of the oestrous cycle with little risk of undesirable effects on the endometrium.
1.Oestrus control  (i) Bitches
Permanent postponement of heat
Repeat injections given in anoestrus/metoestrus induced by the previous administration of Delvosteron.
Temporary postponement of heat
A single injection given in anoestrus.
Suppression of heat
A single injection given at the beginning of pro-oestrus.
Dosage and Administration
Bitches: 10-33 mg/kg bodyweight. The recommended average doses are as follows:
Body weight (kg)
Dose in ml
10 mg/kg
Route of administration
Delvosteron should be given by subcutaneous injection taking special care to ensure that the product is not deposited intradermally or into a pad of subcutaneous fat or scar tissue. The usual aseptic precautions should be observed, i.e. the site to be used should be cleansed and swabbed with spirit. It is helpful to massage the injection site following administration to promote dispersion of the product.
Dosage schedule
Permanent postponement of heat
It is recommended that injections are given as follows:
1st injection in pro-oestrus (see suppression of heat, overleaf), or in anoestrus (see temporary postponement of heat, overleaf).

2nd injection  3 months after 1st injection

3rd injection 4 months after 2nd injection
subsequent injections at 5 monthly intervals.
An injection of Delvosteron may be given to maintain permanent postponement of heat in bitches that are presented late, provided that postponement has not been interrupted by heat.
If anoestrus is not fully maintained, i.e. a `breakthrough' oestrus occurs in bitches on the permanent postponement regime described above, then immediate re-injection is suggested followed by dosing at intervals described above, but starting one step back in the duration of intervals between injections. For example, if a breakthrough heat occurs in a bitch being given injections at 5 monthly intervals, an immediate dose is given, the next dose 4 months later and the subsequent doses at 5 monthly intervals.
Following termination of a permanent postponement course, the next oestrus will occur generally 6-7 months after the last injection. In approximately 4% of cases the interval may be less than 5 months and in 7% it may be longer than 12 months. Up to 3% of bitches may fail to come on heat again when a permanent postponement course is terminated.
Temporary postponement of heat
A single injection given at any time in anoestrus but preferably not more than one month before the effect is required. The subsequent oestrus will occur on average 6 months after the injection. In about 3% of cases the interval will be shorter than 3 months and in up to 4% of bitches the delay will be longer than 12 months.
Suppression of heat
A single injection as soon as possible after the onset of pro-oestrus is seen. Following the injection, bleeding, vulval swelling and attractiveness to dogs should gradually decrease and stop within 5-7 days. The time for return to oestrus in the majority of bitches will be 5-6 months on average, but in approximately 3% of bitches the interval will be shorter than 3 months and in 1% it will be longer than 12 months.
Treatment of false pregnancy
A single dose, given preferably as soon as the signs are seen. In most cases nervous signs will disappear within 6 days and lactation will have stopped or be much reduced by day 9 after injection. In approximately 20% of cases the signs will recur within one month of treatment, about 70% of these cases will respond to a second dose.
Prevention of false pregnancy
Medication for permanent postponement of oestrus as advocated above.
Contra-indications, warnings etc
1.As with all progestagens, the possibility exists that the Cystic Endometrial Hyperplasia/pyometra complex may be seen as a side effect of the medication. In the clinical trials carried out with Delvosteron, however, the incidence of uterine disorders including pyometra, was only 0.3% overall and no cases occurred in bitches injected in pro-oestrus. The incidence of uterine changes was higher (1.4%) in animals which had previously received depot progestagens containing medroxyprogesterone acetate.
2.A transient increased appetite, lethargy and weight gain may be seen in some animals medicated with Delvosteron, but these side effects occur less frequently than with the first generation progestagens such as medroxyprogesterone acetate or megestrol acetate.
3.When using Delvosteron for the suppression of heat, it is important to ensure that the bitch is still in the early stages of pro-oestrus as an injection given in the later stages of pro-oestrus is unlikely to be effective at suppressing heat.
4.Bitches may accept the male for some days after medication with Delvosteron in pro-oestrus (suppression of heat). Thus contact with dogs should be prevented, wherever possible, until the signs of heat, vulval swelling and bleeding have fully regressed. This usually occurs within 5 days of dosing.
In bitches, the duration of postponement of oestrus following a dose of Delvosteron may on occasion be shorter than expected where the medicated animal is housed with other bitches. In such cases contact the Company for advice on possible alternative dosage regimes.
5.Delvosteron has been used to control heat in diabetic animals without altering insulin requirement. However, in other animals, the administration of Delvosteron has led to an increased insulin requirement. It is advised therefore that the product is used with caution in such animals and that urine sugar levels are observed carefully during the month after dosing.
6.A brief pain reaction may be seen immediately after injection. Since a slight local reaction, skin thinning and `pitting' together with some discolouration and loss of hair may occur very occasionally, it is advisable to inject Delvosteron subcutaneously on the medial side of the #### fold in thin skinned or show animals.
7.Very occasionally a local or systemic allergic/anaphylactic reaction may occur, necessitating immediate treatment with an appropriate corticosteroid, antihistamine or adrenaline.
8.Cases of false pregnancy that recur after a second dose of Delvosteron are better treated conservatively (restricted water intake, low carbohydrate diet, increased exercise, etc.) rather than being given further hormone medication. Delvosteron should not be administered to bitches which have been treated previously with oestrogens or other progestagens for the current false pregnancy.
9.A few cases of mammary hypertrophy following the use of Delvosteron in entire and neutered queens have been recorded, but proligestone appears less likely to induce the condition than first generation progestagens.
10.Delvosteron, in common with other progestagens, may cause adrenal suppression in some animals. It may be sensible therefore to administer glucocorticoids to animals being given the product for the permanent postponement of heat if they are subjected to excessive trauma, stress or require major surgery. However no problems have been reported by veterinary surgeons in practice in this respect.
Further information
Although Delvosteron may be used to medicate bitches at their first oestrus, this regime is not normally recommended. Similarly medication before a bitch's first oestrus is not generally advised. Delvosteron may be safely used in breeding bitches, queens or jills; fecundity at the oestrus following the cessation of medication is not adversely affected. Delvosteron is not contra-indicated in bitches with a history of abnormal cycles or those which have shown or are showing signs of urogenital tract disorders. Indeed there is an indication that the product may be used beneficially in such caes; for example the permanent postponement of oestrus with Delvosteron may prevent the recurrence of endometritis.  Delvosteron generally has little effect on the performance of racing greyhounds.
In trials, 65% of cases of allergic skin conditions in dogs responded well to a single dose of 10-33 mg/kg, as recommended for oestrus control in bitches, although not unexpectedly the response was only maintained in just over one third of the cases. Cases of flea hypersensitivity responded particularly well. Dosing with Delvosteron may thus be a useful alternative to medication with glucocorticoids whilst the underlying case is being eliminated

Answer I have used this injection in the past on a couple of my girls and I had no problems at all in getting them in whelp, I had designer genes jabbed for two years then let her have a clear season as was recommended by my vet then we mated her on her next season and she took and produced 9 healthy puppies she also had a further two litters without any problem she lived a full healthy life until we lost her at 12 and a half, with no sign of any mammary tumours at all. Yet I lost my first afghan aged 13 with Mammary Cancer and I'd never had her seasons stopped!
I'm sure I heard somewhere that there is now a new product to stop season that doesn't have male hormone in it maybe someone could enlighten us? Jayne

Answer  that's what I wanted to hear, that you could still get the bitch in whelp at a later date after using Delvosteron as I have heard of bitches being unable to conceive after their owners used other products interfering with the natural cycle and know that at some later stage Cath might want to mate her young bitch. Hazel

Answer  Coming a bit late into this thread  having been "Away" but reading through I note the many comments in regard to CATH's initial question on delvostrone jabs.& your comment on this being a SAFE drug, well ALL DRUGS will have some dangers and NONE could be considered 100per cent safe....these etra emy comments on DELVOSTRONE based on my own experiences in using this drug and on comments from vet experts in Onocology and the "risk factors " associated with mammary tumours.
This topic has been raised before on IAC, and will be amongst the old messages somewhere on line and I have previously made comment myself. so apologies for repeating.. Just just to add to this current thread. At a veterinary talk I attended in 1996 in regards to CANCERs and specifically the MAMMARY TUMOURS, the Onocologists at Cambridge Vet School at that time were adamant that there WAS a significant RISK FACTOR with PROSTAGEN's that are contained in these chemical suppressant drugs to prevent seasons, specifically in those bitches who showed GENETIC SUSCEPTIBILITY to such tumours (same has in HUMAN families)
The Hunting Breeds & those highly In-bred do appear to carry an increased susceptibility & this MUST be addressed when ANY owner decides to embark on a long term programme for the delaying of heats for whatever the reasons.
Many owners may encounter NO problems & will give a perfectly "Safe" History" of having given the drug with NO apparent ill effects....BUT... All bitches are different and what may work for one may NOT work for another. INFORMED CHOICE is the key phrase.
From my own experience in using Delvostrone. My MADAM GAYE had this drug in her later years as we (my vet & I ) felt we were not prepared to risk a surgical spay given her history with GA and Post-Op shock following her ceasarian section in 1991 when she almost died. She went on to develop mammary tumours very quickly and died before the age of 10 years with secondaries in lung & spine (the usual route for secondary deposits)...Her litter sister, my EDITH PIAF, was given just 2 shots only of this same drug and she too later developed tumours...These bitches are from a family that does have an apparent history of mammary tumours, needless to say I have NEVER given this since and would not be prepared to do so unless there was a VERY RELEVANT HEALTH reason and I had weighed up all the relevant factors.
I of course cannot say that these two girls would not have developed tumours had they NOT been given the drug...however 3 of their litter sisters lived to good ages, 13 years plus and one to almost 17 years.
I am aware that a number of owners who have had bitches who have developed one of the blood related Auto-Immune conditions, DO use the drug as the risk factor related to a surgical procedure in this scenario might well be considered to be a greater risk.
Concerning seasons and phantoms. I found that phantoms did STILL continue despite the artificial delaying of the season.
Phantoms can be dealt with in a variety of ways but and I personally would never consider giving delvostone to a bitch who was already exhibiting severe signs of are "playing with the hormones again!....There are a variety of alternative options and many WILL work most successfully, forget just SEPIA and PULSATILLA homoeopathic remedies! ....There are many other affective alternative homoeopathic remedies....once again each bitch is different.
URTICa in LOW potency, *VERY important to remember LOW, will dry up the milk and PHYTOLACCA is a great gland swelling remedy & works well on engorged breast tissue.
Consultation with a Homoeopathic vet may be of help in such a situation.
Of course it is for each owner to make the final decision in what they will choose to do in the best interest for their bitch....NOT just to keep them in coat & prevent seasons for show ring prowess..................Well that is MY view!
I also believe that there are some owners who HAVE experienced difficulties in getting their bitches into whelp following prolonged courses of delvostrone shots (less than 4 years, from what owners have told me,) also if they have got bitches into whelp there have been problems with some of the puppies physical developments...but AGAIN.. this could be open to debate. Sylvia

Answer I have used Delvosteron for many years now. All my dogs live together ( male and female ) and it makes life much easier when we do not have seasons.
My girls have delvosteron on the FIRST /SECOND DAY of colour.I have never given it 4/5 months later.I wait for the season to come round again in a normal way. I have found that some come in at 6 months but others have gone 10 months or even longer.
Regarding litters I have never had a problem. Rhana produced 2 litters of 13 and 11 and had always been on Delvosteron and we did not let her have a normal season befoe mating her. The others had litters ranging from 6 - 10.Again with no normal season before mating them. However I have to say that some still have 'phantoms'. Pat

Answer  I have been watching this string with interest, as I have used Delvosteron many years ago. The vetinary hospital that I used took care to explain that this drug is generally considered safe, but as Sylvia pointed out there have been some reports of adverse effects from the use of progestins. These reports can be seen on the following link, but be aware, it is written for vets! Gerry     comment - well worth a read


Question  Thank you for your very interesting article.I have been following this thread with great interest as both my girls are on Delvosteron.
I have searched the thread looking for an answer to my worries and could not find what I was looking for and wondered perhaps if you could give me any advice on the subject. My concerns are that once you stop giving Delvosteron is there more incidences of pyometra developing?  I understand that this was a problem with the older type drugs. Do you think this could still be a problem nowadays?  My vet has told me that in later life this could be a problem but may have been age induced due to hormonal changes that would occur anyway.
My girl has had three injections and I am now having a great problem with weight gain (despite the fact she is on a permanent diet).
She seems to be carrying a lot of weight over her loins and I wondered perhaps I should take her off the Delvosteron and see if she regains her normal weight. My concerns are that if I do she may go down with pyometra.
I would be so grateful for any advice you could give me regarding this and would really appreciate hearing from anyone who has had problems with pyometra after a supression of heat.  Jackie

Answer  I can only relate my own experience in using this drug (albeit at the time for a valid medical reason as we  preferred NOT to do a surgical spay on a bitch with a high risk factor relating to GA as I tried to explain in my original message) could say it was for CONVENIENCE albeit with an underlying medical reason for that convenience...You say that you are afraid of  PYOMETRA, I think every owner who has a bitch has this FEAR at the back of the mind always.....but "playing with HORMONES could in fact  create even MORE problems...I always say WHAT DO THE VETS & THE DRUG COMPANIES NOT TELL YOU!!....

The following extract may help you....I know it is a bit technical but in short   the incidence of a pyometra  will INCREASE with continuing use of  any drug containing the progestins.

I would agree with your vet that there is a "Grey Area" and who can say if a bitch will or will NOT develop a pyo in middle or late age, maiden or a brood. In fact my own ANGELINA BALLERINA  who NEVER had  any jabs and had a litter at 6 years with NO problems at time of whelping etc, went on to develop a pyometra   at 11 years plus. She was operated on and was fine, she died just  before her 13th birthday.

I had another bitch who we could NEVER get into whelp, she likewise NEVER received any hormonal jabs and she  got a pyometra at 8 years old.

There are many ways of controlling the situation in regard to  early prevention  of phantom Ps and the prevention & certainly early signs of  a potential  risk of  pyometra. The keyword is OBSERVATION of the bitch at all times

 Increased Incidence of Uterine Pathology - High doses of progestin, or repeated or prolonged exposure to moderate doses of progesterone or progestins will cause cystic endometrial hyperplasia (CEH). Cystic endometrial hyperplasia involves proliferation of the glandular endometrium, and cystic dilatation of the endometrial glands with endometrial fluid accumulated in their lumen. The length of the canine luteal phase (2 months) and the relatively high progesterone concentrations during the first third of the progestational phase (15 to 80 ng/ml) predisposes the canine uterus to spontaneously develop CEH, a phenomenon which tends to disappear on itself towards the end of diestrus. CEH is typically an incidental finding, and its natural incidence is not known. CEH generally appears only in areas of the endometrium not supporting a placenta, and develops in a more rapid and intensive way if the uterus has been primed by estrogens ,Exposure of the endometrium to progestins causes proliferation of the superficial layers of the endometrium with increased secretory activity of the endometrial glands, which can lead to CEH ]. CEH predisposes the uterus to infection, typically by otherwise normal vaginal flora, and can result in pyometra. The incidence of pyometra is increased with the use of  progestins

this may interest you given the weight increases you have noted in your bitches.......I certainly had this with the second of my bitches who had the jab and then developed mammary tumours, when we stopped the delvostron, the weight came off!

 Behavioral Modification - Behavioral modification including increased appetite with resulting weight gain, polydipsia and mild depression have been reported with progestin treatment in both the bitch and queen. Progestins have also been reported to cause decreased libido in males, and have been used therapeutically to suppress male libido in both dogs and humans.

 Contraindications for use of Progestins.
Do not treat females that are potentially pregnant, as this may cause fetal developmental defects especially masculinization of females, as well as delay onset of parturition, thereby causing fetal death in utero due to placental detachment.
Do not treat animals with a history of frequent or excessive vaginal discharge.
Do not treat animals with a family history of uterine, mammary or liver disease.
Do not treat diabetic patients.  

Local Skin Alterations - Local skin alteration including skin discoloration, alopecia, skin atrophy, and calcinosis circumscripta have been reported at sites of progestin injections          Sylvia

Question Tinah is on delvasteron too...and my vet advises too every 5 month jab... I don't like the thought of jabbing too much like most of you. Please can you tell me if you jab your girls at the first or second day how the boys react?  Is giving the injection at that moment enough to avoid dogs from being idiots and from fighting? I would love to wait until Tinah starts her season if there is no risk of my boys getting too excited?  Gonny

Answer As I said I wait until we have colour. My vet gives the injection only if we are within 48 hours of colour. After that it is too late. They have a 'season' in so much that they have colour. This lasts about 5 days. My dogs never pester the girls when it is done this way. They all still play happily together. We have done it this way since Delvosteron first came out.( many years now ) I have told other people to do it this way and nobody has had any problems. I feel a lot happier because they are not done every 5 months. Pat

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