Coin Rubbing Part 3: Adverse Complications

My wife lives by the idea that medicine is a double sided sword and I have generally found that to be true more often than not. It was a shock to me when I learned that medicines I had considered benign as a child could actually have some pretty nasty side effects (ibuprofen, aspirin, etc...). Additionally, I am aware that traditional or alternative therapies that claim to have few side effects can often have disastrous ramifications. While I was volunteering with Operation Smile Cambodia I saw a horde of Cambodians that came through screening with extensive scars resulting from serious burns associated with "cupping".

Coming from this experience and perspective I expected to find at least some adverse side effects of coin rubbing. Surely there should be some physiological ramifications. Long term dermatological issues? Problems in pregnant women? Permanent damage to infants? Blood poisoning? I have not been able to find reports of any of these problems. Indeed it seems that the psychological ramifications of the "child abuse" label in the U.S. may be the most serious side effect (Besides, of course, the pain, discomfort and bleeding that accompanies the process). To some extent I am disappointed. While it would be wonderful to have a healing method that treats a variety of symptoms with absolutely no long term drawbacks, the absence of any complications tempts me to doubt its authenticity. If a procedure does something physiologically significant, the pathways should be able to cause harm as well as heal. I understand that many alternative healing methods follow the mantra that we need to open pathways to "allow the body to heal itself". Even the body's healing mechanisms have the potential to cause serious harm however (autoimmune disease, prolonged fever, clotting or lack thereof). On the other hand maybe the visible temporary side effects, which could cause nerve desensitization and increased circulation, are more than adequate and I am making something out of nothing.  

The only reports that I was able to find that relate at all to dangerous coin rubbing side effects addressed camphor intoxication and burns (associated with some practitioners who heat the oil they use).

Camphor Intoxication After Cao Gio (Coin Rubbing)

Cutaneous Side Effects of Alternative Therapy