New Mexico is the only state that explicitly allows people with PTSD to smoke pot under its medical marijuana law - an issue that is getting attention around the country at a time when traumatized vets are coming home from wars in Iraq and Afghanistan in large numbers.
New Mexico's medical marijuana law has created a conundrum for the Veterans Affairs, which does not allow its doctors to prescribe pot because the drug is illegal in the eyes of the federal government. So, patients like Culkin must seek out an endorsement from a private doctor.
PTSD accounts for more patients than any other of the state's 16 eligible debilitating conditions approved for medical marijuana treatment.
Culkin wishes the VA could provide it.
"Oh my God, it would be so helpful," said Culkin, 30, who heads the New Mexico Medical Marijuana Patients Group formed last December as a support and education group.
If the VA handled all needs - including medical cannabis - care for veterans would improve, he said, because the doctor would know everything about the patient.
"If these guys fought the hardest they could, why not give them the best medicine, or an alternative medicine you can?" Culkin said.
States where medical marijuana use has been approved have been trying to determine what ailments the drug will help. Those efforts have resulted in a mishmash of regulations.
For instance, a Colorado House committee in March rejected following New Mexico's lead in specifically listing PTSD to qualify for medical marijuana. California doctors can recommend medical marijuana for a variety of conditions and "any other illness for which marijuana provides relief."
The American Medical Association has called for controlled studies of marijuana for patients whose conditions it might help. The association also wants a review of marijuana's status as a Schedule 1 drug so clinical research can move ahead.
The Department of Veterans Affairs says it is developing a national policy, and the head of Veterans for Medical Marijuana Access believes a VA policy allowing medical marijuana "is inevitable."
"We're all on the same side," said Michael Krawitz of Virginia. "My goal is a good outcome for the veteran, and that's their goal."
"The irony in this ... is it's a common thing for veterans to tell me, 'The VA is telling me if I just stay away from medical marijuana, we'll give you all the pills you want, morphine, whatever,'" he said.
Krawitz, 47, was severely injured in a motorcycle accident while stationed in Guam with the Air Force about 20 years ago and eventually received a medical discharge.
He is an advocate for marijuana's medicinal benefits.
"It makes it so you can put down a lot of the pain pills. It helps with nerve pain, that really bad spasming and twitching."
He praises the care he's gotten from the VA, but adds: "I feel sorry for the VA; they're caught in the middle ... They have a clear mandate to take care of veterans."
Given their inability to get medical marijuana from the VA, New Mexico veterans are finding their own go-to physicians, including Dr. Eve Elting in the central part of the state.
"I have guys coming to see me from all over the state, five or six hours' drive, just to be legal," said Elting, of Truth or Consequences. "It's bad enough they have something that makes life so challenging. On top of that they're discriminated against, made to feel like they're doing something wrong."
Elting said veterans hear about her by word of mouth since she will see people who aren't regular patients. About a quarter of those who come to her want medical marijuana for PTSD. One day she saw eight veterans - five for PTSD.
New Mexico doctors do not prescribe medical cannabis. Rather, they certify someone has one of the approved conditions and that standard treatment doesn't work. Patients then apply to the state program. If an application is approved, the patient gets a registry ID card that allows possession of up to 6 ounces of medical marijuana.
A psychiatrist's diagnosis must be included for PTSD. For chronic pain, X-rays or CT scans are required and both a primary doctor and a specialist have to sign off.
"Even though the VA has prohibited them from signing the documents, I don't see why a physician treating the veteran would not be willing to sign a piece of paper attesting that the patient had that condition," said Elting, who did her residency at a VA hospital and serves on New Mexico's eight-member medical advisory board for the program.
Veterans armed with Elting's signature would still have to find a private psychiatrist or other specialist to sign.
"Everyone's happy to give them a million narcotics, anti-psychotics. It's frustrating," she said.