How long to wait before starting DTPA chelation. July 2025 recommendations.

How long to wait till starting chelation with iv DTPA.

My general recommendation has been to wait 3 months. The rationale for this is two reasons: 1. a sizable number of individuals, maybe 1/3, will recover generally on their own, with conservative measures (healthy eating, some supplements, gentle exercise, sauna) and 2. Waiting 3 months allows for some native dampening of the immune system to Gd, to minimize intense Gd- removal Flare with chelation. This approach really works best with people who received 1 GBCA injection. Assessment for using this approach (still)  includes that the patient's symptoms starting at 45 days post GBCA injection,  are getting less. Then watchful waiting to 3 months (and if still symptom decreasing), extending to 6 months, and so on. Usually ideal windows to achieve maximal benefit to near cure with chelation is starting to mature/ diminish when chelation initiated at 1 years to 2 years. Beyond 2 years, near cure from chelation has dropped in likelihood, but is still present. There is no time post GBCA injection that DTPA chelation will not result in significant patient benefit.

Presently, since with a lot of experience, we have found our regimen of iv steroids at time of chelation, and use of an oral steroid taper (FRAME technique) and antihistamines have been effective at controlling severe Flare, I recommend patients look at starting chelation at 2 months (even earlier) if warranted. This is the situation when symptoms at 45 days are not diminishing, or even plateauing, but are increasing. Earlier than 3 month chelation is indicated in these individuals. But iv steroids and full FRAME drugs are essential and not optional, as the immune system is now in a heightened maximal state of reactivity to Gd.

The most recent addition is to chelate within 14 days of  chelation. 10-14 days has been shown to be the time lag between administering a vaccine for a particular entity (such as COVID) and the immune system fully charged to react against the presence of the entity. So using this same reasoning, to chelate earlier than 10 days after GBCA injection, you are chelating at a time that the immune system is not fully charged to result in maximal Flare reaction to the movement of Gd (which DTPA essentially causes). So this early time for chelation takes advantage of the fact that the immune system is not fully armed to result in massive Flare. In many respects this is a slight time extension of concurrent chelation with GBCA injection, which both Omniscan and Optimark do by virtue of having excess 'free' ligand administered in the GBCA. Omniscan with 5%, Optimark with 10%. This has been our theory in the article we wrote comparing these agents, that accounts for why Optimark results in proportionally fewer cases of NSF (GISF - Gad induced systemic fibrosis). More Gd is essentially being picked up by the free ligand, when Gd is dislodged from the administered GBCA. We have limited experience with very early chelation, because usually by the time the patient has made the diagnosis on themselves (since presently most physicians seem unwilling or unable to do so) they are beyond 14 days of getting the GBCA injection. Even with limited experience our theory has been shown to hold up. This concurrent chelation has occurred then in atleast 80 million doses of Omniscan and 40 million of Optimark.So there actually is virtually unmatched level of clinical experience with the value of very early chelation, comparing to nearly all other medications.These numbers reflect the number of administrations of these agents that have occurred world-wide. The request for extremely earlier chelation really is initiated by the patient,: they received a GBCA injection, GDD symptoms severe from the start and getting intolerable by 1 week.

The extrapolation of chelating within a 10 day window for GDD, my opinion is that everyone who is managed with steroid/antihistamine for severe acute hypersensitivity reaction (AHR) to  a GBCA, should get atleast 1 vial of 1 g of Ca-DTPA, in addition to iv steroids and antihistamines.. Everyone who receives Gd retains Gd in their body. So if they have shown they can generate a severe AHR they still have that menace residing in their body. Perhaps a second vial of Ca-DTPA the next day. I do not know what percentage of those who develop severe AHR go on to develop GDD. It is reasonable to project that 1/2 of them do. Presently, since I chelate in a small clinic I have not chelated any patient who reports near fatal severe AHR to GDD, and I recommend to them they have to go to a hospital to get this done, so they are in a circumstance where near fatal AHR can be treated with blood pressors, epinephrine, etc. Unfortunately this generally means they don't get chelated. This would mean all Radiology departments and all Emergency Departments should stock Ca-DTPA. I prefer Ca-DTPA over Zn-DTPA as it removes more Gd, and this is likely imperative since most GBCAs will be fully intact when the individual is experiencing severe AHR..

A side note, we have never experienced a severe AHR to DTPA chelation of GDD, regardless of the GDD severity. This does reflect the nuances of how the immune system can go awry, and the cascades of reaction to various immune system perturbations.

Richard Semelka, MD