Soft strains of classical music fill the waiting room as a smiling woman in a white lab coat hands you a form to fill out and asks if you’d like some organic lemon ginger tea or water.

Relaxing into a leather recliner with your pen and paper, you might feel as if you’ve landed in an upscale spa. But in fact you’ve come here, to Colon Care, for one reason and one reason only: to have 23 gallons of water released into — and out of — your large intestine.

Via a tube inserted into your bum.

We’re talking colon hydrotherapy. As in colonics. As in a monster enema that empties your guts and leaves you feeling 5 pounds lighter and five years younger (at least that’s one theory).

Though not everyone agrees they are good for you, colonics are the rage in major cities, including Portland, where at least three colon hydrotherapy practices report that business is booming.

“People have a false impression of colon hydrotherapy based on what it used to be — a bucket with a hose on it,” says Rebecca Harder, the certified colon hydrotherapist who operates Colon Care in the Riverplace Medical Building. “But colonics have come a long way.”

High colonics, the granddaddy of all purgatives, involve injecting a large amount of water into a person’s colon for the purpose of cleansing and flushing out the large intestine. Once the fodder of jokes and the stuff of celebrities, hippies and health nuts, colonics are now flirting with mainstream status.

And they are taken very seriously — by their grass-roots and Internet-driven following.

“Fourteen years ago people hadn’t heard that much about colon hydrotherapy, and I felt like I was having to explain myself and my profession constantly,” says Jill Simons, owner of All’s Well That Ends Well, a colon hydrotherapy business inside Circle Healthcare clinic on Northeast 28th Avenue. “Now we have people coming in who saw something about colonics on ‘Oprah.’ They’ve read about colonics on the Web or they’ve read about them in diet books.”

On the east side, colonics still maintain their alt cred in the humble environs of basements and holistic health clinics. But on the west side, they have gone distinctly uptown thanks to Colon Care, one of several posh colon hydrotherapy operations that have opened in larger U.S. cities in recent years.

Harder says that 80 percent of her clients are referred by physicians and that 10 to 15 percent of those referrals are from mainstream medical doctors who send patients in for relief from constipation or to prep for a colonoscopy. The rest of the referrals come from naturopaths and other alternative health practitioners, many of whom suggest colonics as part of their seasonal cleansing protocols.

But while colonics may be gaining acceptance on a grass-roots level, they are still widely criticized by regular medical doctors. Even Portland-area MDs who refer clients to colon hydrotherapists declined to be interviewed for this article.

However, Dr. Daniel Herzig, an assistant professor of surgery at Oregon Health & Science University, was willing to talk. The colorectal surgeon noted that all types of colon cleansing, including hospital-administered laxatives and enemas, carry some risk of complication.

Colonics are no exception, but because they are largely unmonitored by state or federal government, there is no way to track problems that may arise, he said.

“Are they safe? The question really is, ‘Has their safety ever been proven?’ People who give them will say, ‘They’ve been done millions of times and we don’t know of a single complication.’ But they’re not really regulated as a medical procedure. When we do a procedure in surgery, we have a quality-assurance process, a peer review process and continuous monitoring.”

Dr. Maggie Yu of Sherwood Family Medicine, a holistic health care practice that employs both medical doctors and naturopaths, agrees there is need for oversight. But she says her clinic has referred patients to colon hydrotherapists for years and seen no deleterious effects.

Often, a physician in her office will provide a referral after patients ask about colonics for conditions such as constipation and irritable bowel syndrome, she said. “There are no major medical studies showing there are any medical benefits to colonics. But anecdotally, patients with these conditions tell us they feel better after colonics.”

Both Harder and Simons are certified through the International Association for Colon Hydrotherapy (IACH), and both use machines that have been approved by the Food and Drug Administration as Class 2 medical devices. But other than that, there is little oversight of the field, something they would like to see changed. Both support state licensing for colon hydrotherapists in Oregon. Only one state, Florida, currently requires licensing.

Harder says she believes licensing will help allay fears that many people have about getting colonics. The procedure can seem a little daunting to the uninitiated.

Colon hydrotherapists argue that when the procedure is done correctly by a qualified practitioner on a client who presents no contraindications, there are few risks. Contraindications include obvious rectal bleeding, bleeding ulcers and certain types of ulcerative colitis. And while the cleansing benefits are not backed by research, the response from clients who get colonics for that reason has been overwhelmingly positive, they say.

Harder, 42, says she seeks to collaborate with medical doctors, many of whom are more open to colonics than they used to be thanks to the growing field of integrative medicine.

She cites research by Dr. Joseph Fiorito, a Connecticut gastroenterologist. The study presented to the 2006 meeting of the American College of Gastroenterology found that colonics were an effective treatment for prepping the colon for colonoscopy.

Services don’t come cheap. At Colon Care, new clients are required to purchase a $285 package that includes an hourlong sit-down orientation with Harder and two 90-minute colonics.

Simons, 40, co-owns All’s Well with certified colon hydrotherapist Paddy Lazar, 62. A colonic there costs $75 for the first session, which includes an orientation, and $70 for subsequent sessions.

“It used to be that we did a lot of educational workshops and free lectures. Now I’m pretty floored at all the ways people find us,” Simons says. “We’ll have several months a year where we have waiting lists.”

So why the colonics craze? According to Simons, it may have to do with the growing national obsession with detoxification, the purported process of removing environmental, food and drug toxins from the body via a number of protocols. A slew of recent documentaries address nutritional cleansing, as do many social media websites. Raw food restaurants, juice bars and colon cleansing pills, powders and potions are everywhere, and the Internet is loaded with tips for detoxifying with foods, supplements and colonics.

Chakra 17, a colon hydrotherapy business in Southeast Portland, enjoys a cultlike following. And while the low-key basement operation may appear to be the most humble of the three, owner Alex Steury is a much-sought-after practitioner — partly because of his peaceful countenance that belies his 29 years — and partly because of his training. His eight-month internship was carried out under Wendy Jones, who was a much-sought-after practitioner in New York City, catering to celebrities, millionaires and nutrition writers, among others, before she opened a second location in Portland.

Jones, in turn, was trained by East Coast colonics guru Gil Jacobs, who has trained scores of therapists in the New York City area, including those who operate Love Your Transformation, the ultra-trendy Manhattan colon hydrotherapy “treatment center” that caters to VIPs.

Those trained by Jacobs and his students are known as “gravity colon hydrotherapists” because they use very basic equipment that relies only on gravity for power.

One of the earliest American proponents of colonics was John Harvey Kellogg, M.D., the founder of the Kellogg cereal company. He is credited with helping to make colonics popular among conventional physicians from the early 1900s through the 1940s, when they were used to treat such conditions as depression and arthritis. But as seemingly old-fashioned practices were dropped in favor of laxatives and drug-based therapies, colonics lost favor in mainstream medicine.

Colon hydrotherapists say they believe it’s only a matter of time before the therapy gains an even wider acceptance with the public and, eventually, with the medical establishment.