Real Simple gives walk-in health clinics, now popping up everywhere, a checkup.

At a 24-Hour Clinic
Who's on call: An M.D.

Services offered: Treatment for conditions such as fevers and minor cuts that require stitches.

The details: Sickness doesn’t always happen between 8 and 5, and walk-in multi-specialty clinics with extended hours have become less costly alternatives to an emergency-room visit for both minor and urgent problems. In general, you’ll see a doctor within 30 minutes (not so in most ERs), and there might even be specialists on staff, from a pediatrician to an allergist. You’ll find these clinics everywhere, from small towns to big cities.

In New York City, for example, the Beth Israel Medical Group opened a stand-alone facility in a neighborhood with an especially busy nightlife. In Overland Park, Kansas, the Children’s Mercy South Urgent Care Center of Children’s Mercy Hospitals & Clinics is staffed by a team of pediatricians and pediatric nurses. And 24-Hour Urgent Care, in Temecula, Calif., employs an orthopedic surgeon for walk-in consultations. To locate a clinic near you, go to wheretofindcare.com or concentra.com.

Cost: Up to $150 for a visit. Some locations accept insurance.

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Who's on call: An M.D. (possibly even your own).

Services offered: General consultations and second opinions.

The details: If your doctor subscribes to a service such as Relay Health or Intuit Health, you can log on to the website to get in touch with her virtually—for information about a new medication, say, or to ask a follow-up question after an in-office appointment. If you have already seen a doctor about a problem but want a second opinion on a prescribed course of treatment, online consultants at the Cleveland Clinic’s MyConsult and the Massachusetts General Hospital–affiliated Partners Online Specialty Consultations can help. You fill out a detailed medical history, choose the consultant you would like to have weigh in (if you wish), have your doctor fax records if necessary, and receive feedback in about a week.

Cost: An online consultation with your own doctor is typically the price of your insurance copay, but not all insurance plans cover virtual visits. Second opinions may also not be covered and can cost hundreds of dollars.

At the Drugstore
Who's on call: A nurse practitioner.

Services offered: Treatment for minor illnesses and injuries (a sore throat, a twisted ankle) and administration of vaccines, including flu shots.

The details: Health clinics that offer first-come, first-served walk-in appointments are now open in national chains—including CVS, Walmart, and Walgreens — as well as some mom-and-pop pharmacies. They’re particularly popular for flu shots.

(For children’s vaccinations, it’s best to see your pediatrician or family physician, says Glen Stream, the president-elect of the American Academy of Family Physicians: “This way, you keep the child’s records complete and in one place.”) And, of course, while you’re there, you can also ask the pharmacist drug-related questions, including how and when to take a medication or how a certain pill interacts with other drugs.

Cost: Flu shots are about $30. Visits for other reasons can cost up to $150. Most pharmacy clinics accept insurance. (Advice from the pharmacist is free.)

At a Hotel
Who's on call: An M.D.

Services offered: Everything you could get from your primary-care physician, in the privacy of your room.

The details: Some major hotel chains, including Four Seasons Hotels and Resorts and the Morgans Hotel Group, typically have a doctor available around the clock. You’ll usually begin with a phone consultation, and depending on your symptoms, the doctor may give you a full exam in your room. He might bring along frequently prescribed drugs to save you a trip to a pharmacy or wheel in a mobile X-ray or ultrasound machine. If your hotel doesn’t have a doctor on call, go to innhousedoctor.com to find a medical professional who makes hotel visits.

Cost: Fees for in-room examinations with an on-call doctor may be more expensive than an office visit at home. These doctors may not accept your insurance, and full payment is due at the time of the appointment. But they should be able to give you a bill that you can submit to your health-care plan for possible reimbursement. Some exotic or luxury resorts, such as the Irotama Resort, in Santa Marta, Colombia, operate full-time medical centers located on the hotel properties that guests can use for a small fee (about $2).

“The hotel picks up the rest of the bill,” says Jose David Florez, the physician at the resort.

At the Supermarket
Who's on call: A nurse practitioner.

Services offered: Treatment of minor illnesses (stuffy sinuses, rashes, ear and eye infections), as well as administration of preventive screenings (for conditions such as high blood pressure and diabetes) and flu shots.

The details: Grocery-store clinics are usually run by independent medical companies. If the staff nurse is busy when you check in, she might take your cell-phone number so you can shop until she calls. When you’re up, you’ll go into an exam room (usually located near the pharmacy or the front registers) for the consultation. Many clinics will send a record of your visit to your primary-care physician afterward for a follow-up, if necessary. And if your problem requires a doctor’s care and you need a local referral, you can get one. To find a supermarket clinic near you, log on to ccaclinics.org (which operates more than 1,200 retail clinics across the country) or thelittleclinic.com (with locations in Publix, Krogers, and other stores).

Cost: $30 to $110. Most accept insurance.

At Work
Who's on call: An M.D., plus nurse practitioners or medical assistants.

Services offered: Standard care for problems like a lingering cough, as well as wellness programs for weight management, diabetes, and smoking cessation that complement your employer’s health-insurance plan.

The details: With care just an elevator ride away, it’s easy to walk in and be back at your desk within a half hour. That makes workplace clinics an appealing option not just for you but also for your employer, who benefits from increased productivity and reduced health-insurance costs.

“We can expect to see office-based clinics become a significant part of the medical-care system,” says Patti Friedman, a senior consultant at Towers Watson, a professional-services company in New York City. In fact, one in three large-scale companies plans to have an on-site medical clinic starting in 2011. (Check with your benefits department to find out if yours is one of them.) Some employers extend coverage to dependents and retired employees.

Cost: In most cases, there is none.

At the Airport
Who's on call: An M.D., a nurse practitioner, registered nurses, physician assistants, and medical assistants.

Services offered: Treatment of common travelers’ afflictions, such as strained shoulder muscles, earaches, and upset stomachs.

The details: Small walk-in clinics can now be found in some major U.S. airport terminals. In addition to medical care, they offer travel first-aid kits, which include things like aspirin, antibiotic ointment, and bandages. They can also bring you up to date on required immunizations that you may have overlooked when planning your trip. Some offer pharmacy services if you forgot to fill a prescription in your dash to the airport. For serious problems that require X-rays or stitches, some larger airports, including Los Angeles International Airport, Hartsfield–Jackson Atlanta International Airport, and Boston’s Logan International Airport, provide van service to a medical facility nearby. Log on to concentra.com to search for airport walk-in centers by city.

Cost: $95 to $200 a visit. Most accept insurance.