A review of IV Hydro Pros, which has had a presence at Spartan Races and Savage Race this year. As the article notes, you are responsible for knowing what goes into your body, and keeping up with what is legal to use.
At present, the use of IV Hydro Pros is currently legal under the standards for OCR Elite/Pro Racers until such a time Spartan, OCRWCs or any other governing body officially takes a stance or statement to the contrary on the matter. Athletes, ultimately, are still responsible for knowing what is going into their bodies but you are not breaking any rules by simply going the IV route. My recommendation is after your race, give Chris and IV Hydro Pros a visit. The service and care provided is top notch and I see them growing as athletes and participants learn how to manage and maintain their bodies. This option is going to grow rapidly in popularity because results speak for themselves and they are noticeable, not marginal.