Medical equipment is still strewn around the house of Rick Lucas, 62, who came home from the hospital nearly two years ago. He picks up a spirometer, a device that measures lung capacity, and takes a deep breath, though not as deep as he'd like.

Still, he has come a long way for someone who spent more than three months on a ventilator because of COVID-19.

"I'm almost normal now," he says. "I was thrilled when I could walk to the mailbox. Now we're walking all over town."

Rick is one of the many patients who, in his quest to get better, found his way to a specialized clinic for those suffering from long COVID symptoms.

Many big medical centers have established their own programs, and a crowd-sourced project counted more than 400 clinics nationwide. Even so, there's no standard protocol for treatment, and experts are casting a wide net for cures, with very few ready for formal clinical trials. In the absence of proven treatments, clinicians are doing whatever they can to help their patients.

"People like myself are getting a little bit out over my skis, looking for things that I can try," says Dr. Stephen Heyman, a pulmonologist who treats Lucas at the long COVID clinic at Ascension Saint Thomas in Nashville.

A bumpy road to 'almost normal'

It's not clear just how many people have suffered from symptoms of long COVID. Estimates vary widely from study to study, often because the definition of long COVID itself varies. But even using the more conservative estimates would still mean that millions of people have likely developed the condition after being infected.

For some, the lingering symptoms are worse than the initial bout of COVID-19.

Others, like Rick, were on death's door and have just had more of a rollercoaster of recovery than you'd otherwise expect. He had brain fog, fatigue and depression. He'd start getting his energy back, then try some light yard work and end up in the hospital with pneumonia. It wasn't clear which ailments were a result of being on a ventilator so long and which were due to what was still a new, mysterious condition called long COVID.

"I was wanting to go to work four months after I got home," Rick says over the laughter of his wife and primary caregiver, Cinde Lucas.

"I said, 'you know what, just get up and go. You can't drive. You can't walk. But go in for an interview. Let's see how that works,'" she recalls.

Rick did get back to work, eventually.

Earlier this year, he started taking short-term assignments in his old field as a nursing home administrator, but he's still on partial disability.

There's no telling why Lucas has mostly recovered and so many haven't shaken their symptoms, even years later. What treatments work, and what recovery looks like, is unique to each long COVID patient.

"There is absolutely nothing anywhere that's clear about long COVID," says Dr. Steven Deeks, an infectious disease specialist at the University of California, San Francisco. "We have a guess at how frequently it happens. But right now, everyone's in a data-free zone."

Researchers like Deeks are still trying to establish the underlying causes — some of the theories include persistent inflammation, auto-immunity and bits of the virus left in the body. Deeks says institutions need more money to start regional centers of excellence to bring together physicians from various specialties to treat patients and research therapies.

Patients are desperate and willing to try anything in order to feel normal again. And often they're posting their personal anecdotes online.

"I'm following this stuff on social media, looking for a home run," Deeks says.

The National Institutes of Health is promising big advances in the near future through the RECOVER Initiative, involving thousands of patients and hundreds of researchers.

"Given the widespread and diverse impact the virus has on the human body, it is unlikely that there will be one cure, one treatment," Dr. Gary Gibbons, director of the National Heart, Lung, and Blood Institute, wrote in an email to NPR. "It is important that we help find solutions for everyone. This is why there will be multiple clinical trials over the coming months."

Trial and error

There's some tension building in the medical community on what appears to be a grab bag approach in treating long COVID ahead of big clinical trials. Some clinicians are more hesitant to try therapies before they're supported by research.

Dr. Kristin Englund, who oversees more than 2,000 long COVID patients at the Cleveland Clinic, says a bunch of one-patient experiments could muddy the waters for research. She says she encouraged her team to stick with "evidence-based medicine."

"I'd rather not just kind of one-off trying things with people, because we really do need to get more data and evidence-based data," she says, "We need to try to put things in some sort of a protocol moving forward."

It's not that she lacks the urgency. Englund has experienced her own long COVID symptoms. She felt terrible for months after getting sick in 2020, "literally taking naps on the floor of my office in the afternoon, " she says.

More than anything, she says these long COVID clinics need to validate patients' experiences with their illness and give them some hope. She tries to stick with proven therapies.

For example, some patients with long COVID develop POTS – a syndrome that causes dizziness and their heart to race when they stand up. Those are symptoms that Englund generally knows how to treat, but it's not as straightforward with other patients.

At Englund's long COVID clinic, there's a lot of focus on diet, sleep, meditation and slowly increasing physical activity. But some doctors are willing to throw all sorts of treatments at the wall to see what might stick.

At the Lucas house in Tennessee, the kitchen counter can barely contain all the pill bottles of supplements and prescriptions. One is a drug for memory. "We discovered his memory was worse [after taking it]," Cinde says.

Other treatments, however, seemed to have really helped. Cinde asked their doctor, Stephen Heyman, about testosterone for her husband's energy. After doing some research, Heyman agreed to give it a shot.

He's trying medications — treatment used for addiction or combinations of drugs used for cholesterol and blood clots — that have been seen as potentially promising for long COVID. And he's considered becoming a bit of a guinea pig himself.

Heyman has been up and down with his own long COVID symptoms.

At one point, he thought he was past the memory lapses and breathing trouble. Then he caught the virus a second time and feels more fatigued than ever.

"I don't think I can wait for somebody to tell me what I need to do," Heyman says. "I'm going to have to use my expertise to try and find out why I don't feel well."

This story comes from NPR's reporting partnership with Nashville Public Radio and KHN (Kaiser Health News).