low insulin test


My small horse (approx. 800 lbs) was originally tested for insulin at 140 (range 10-30).  She's on 100 mg capsule once a day of cyproheptadine.  The most recent test came in as 6 (again range 10-30).  I'm wondering if I could reduce dosage of cypro to every other day or every day and a half.  She has no symptoms at this time of cushings.  She had a slight case of laminitis in one hoof in Feb. 2014.  However, I do not let her on grass.  She's old and has bad teeth.  I give her approx. 7 lbs. senior a day (divided into 4 feedings) but she is also able to eat some hay.

Judy Beumer

Kerry Isherwood

Hi Judy,

To help get things moving along for you, will you furnish dates these insulin tests were drawn, what lab, units of measure used in results (uU/ml, etc), and what brand of Senior grain you are feeding? also if glucose and/or leptin blood results were obtained aling w the insulin? Cyproheptadine as a treatment for IR/EMS is new to me (I have two IRs!) so I will be interested to hear what others suggest.

Thanks! Soon more official help will be sent your way but if you want to start gathering the above info it will help us help you even faster!

Kerry in NY
Sept 2014


Thank you Kerry.  Star's insulin blood draw for test was taken 5/15/15.  It was handled by Clinilab in Valparaiso IN.  Report date is 5/16/15.  Units are uIU/mL, CPS 260,443, equine range 10-30, result 6.18.  I feed Triple Crown Senior.  She does eat some hay.  She was put on Pegolide first but it affected her appetite a lot.  I've had 3 horses on pergolide or cypro and it has always lowered insulin, so I'm surprised you've never heard of them for IR.  My first one was in 2003.  His insulin was over 300 and he was too heavy at that time.  On cypro, his insulin came down to normal and he lost a lot of weight which made him a normal weight.

So I wonder if it's OK to give less than 100 mg a day.  I was thinking of every day and a half.

Thanks again,
Judy Beumer

Nancy C

Hi Judy and Kerry

The use of Cypro has been followed here since 2000.  Here are a couple of early messages.


More from Dr Kellon

And info in the files.


In the early years Cypro was recommended to use to bring down insulin.  There is little research to show it works and the majority of members who have used it found it did not. Cypro has most recently been suggested by researchers (without additional research) and the pharmaceutical company funding them, to be used when the recommended dose of 3 mg of Prascend does not work to control PPID.

Judy - a very likely possibility with your current blood work is error through mishandling but we could use a lot more detail.  Was there a glucose taken as well?    Appetite issue with pergolide can be helped iwth the use of adaptogens, ie APF. It is usually transient. Uncontrolled PPID does affect insulin, so having the Cushing's under control is needed.  Might you have a Case History on Star?  Seeing the big picture would be a big help.

Nancy C in NH
ECIR Moderator 2003
FACT:  With over 12,000 members and thousands of detailed case histories the ECIR Group has made it possible to spot patterns, many of which have been confirmed later by formal study.  See  E. M. Kellon, VMD, The Internet as an Epidemiological Tool, 2013 NO Laminitis! Proceedings, Equine Cushing's and Insulin Resistance Group Inc.