Using Health Services: The Complete Guide

A practical guide to finding your way around US health care: choosing a primary care doctor, deciding between a nurse line, urgent care and the ER, getting referrals and approvals, having tests, leaving the hospital, and using your rights to your own records. For anyone who wants to get the right care, in the right place, with fewer surprises.

Key numbers at a glance

How the pieces of US health care fit together

Health care in the United States is not one system but a set of separate services, each paid for and organized a little differently. Your primary care provider is meant to be the hub: the person who knows your history, handles most everyday problems and preventive care, and refers you to specialists when needed. Around that hub sit specialists, hospitals, imaging centers and labs, pharmacies, urgent care centers, telehealth services and the emergency room.

Insurance shapes how you move between them. Your plan decides which doctors and facilities are in its network, whether you need a referral to see a specialist, and which tests and treatments need approval in advance. That is why the same visit can cost very different amounts depending on where you go and whether the paperwork was done first. Knowing the rules of your own plan, which are set out in its Summary of Benefits and Coverage, saves money and frustration.

The rest of this guide walks through each part of the system in the order most people meet it, explaining not just what to do but why the steps exist. Knowing why a rule is there makes it far easier to work with it, or to push back when it is being applied wrongly. Wherever a rule seems to stand between you and urgent care, remember that emergencies always come first.

Finding a primary care doctor

A primary care provider may be a family medicine doctor, who sees all ages; an internal medicine doctor, who sees adults; or a pediatrician, who sees children. Nurse practitioners and physician assistants also provide primary care in many practices. Having a regular clinician matters because preventive care, prescriptions, referrals and follow-up all run more smoothly through someone who already knows you, and many health plans, especially HMOs, require you to name one.

The best time to find a doctor is before you are ill. Some practices have long waits for new patients, and it is much harder to search when you feel unwell. Start with your insurer's online directory so that your visits are covered at the in-network rate, but then call the office to confirm. Directory listings can be out of date, and you want to know that the practice accepts your specific plan and is taking new patients.

When you call, ask about the things that will matter on a bad day: whether they offer same-day sick visits, telehealth appointments, a patient portal for messages and results, and an after-hours line. Bring your medicine list and any past records to your first visit, or ask your previous doctor to send them. If the fit does not feel right after a visit or two, it is fine to change; a good working relationship is worth looking for.

Checkups and preventive care

Most health plans cover a yearly checkup and recommended screenings and vaccines without a copay when you use an in-network provider, under the Affordable Care Act. People with Medicare are covered for a yearly Annual Wellness Visit, which focuses on a personalized prevention plan. If you have no insurance, community health centers provide primary care and charge on a sliding scale based on your income, and they serve patients regardless of ability to pay.

Getting the most from an appointment

Primary care visits are often short, so preparation pays off. Before you go, write down your main concern in a sentence or two, when it started and what makes it better or worse. List every medicine you take, including over-the-counter products, vitamins and supplements, with the doses, or bring the bottles. Put your most important question first, because the last question asked at the door often gets the least time.

During the visit, be specific and honest, including about alcohol, smoking, sexual health or not taking a medicine as prescribed. Doctors hear all of these every day, and leaving them out can lead to the wrong advice. If you do not understand a term or a plan, ask the doctor to explain it again in plain language; repeating back what you heard is a good way to check. You can bring a friend or family member to take notes, and if English is not your first language, ask for a professional interpreter rather than relying on a relative.

Before you leave, make sure you know what happens next: whether tests or a referral have been ordered, how you will hear about results, when to come back, and what symptoms should prompt you to call sooner. Your patient portal is useful afterward for checking the visit summary and sending non-urgent follow-up questions. It is not the place for urgent problems, since messages may not be read for a day or more.

Language and disability access

If you need help communicating, ask for it when you book rather than on the day. Most hospitals and practices that receive federal funding must offer free language assistance, including qualified interpreters, and reasonable accommodations for people with disabilities, such as sign language interpreters, large-print materials or extra time. Using a trained interpreter rather than a child or relative protects your privacy and reduces the risk of misunderstandings about diagnoses, doses and consent. If help is not offered, ask the practice manager or the hospital's patient advocate.

Nurse lines, telehealth and urgent care

Between your regular doctor and the ER sits a set of options designed for problems that need advice or attention soon but are not life-threatening. They are often the fastest way to find out whether you need the ER, a doctor's visit, a trip to the pharmacy or simply rest at home. Save the key numbers in your phone now, before you need them.

Many insurers offer a free nurse advice line staffed 24 hours a day, and the number is usually on your insurance card. Most primary care offices also have an on-call clinician who can be reached through the practice number outside office hours. Telehealth, meaning video or phone visits, works well for many minor illnesses, medicine questions, mental health care and follow-up appointments, and it usually costs less than an in-person visit.

Urgent care centers take walk-in patients for problems that need same-day attention, such as sprains, minor cuts that may need stitches, earaches, sore throats, urinary symptoms or a rash. They generally cost much less than the ER and have shorter waits. Before you go, check that the center is in your plan's network, and bring your insurance card and medicine list.

Making the call useful

When you call a nurse line or start a telehealth visit, have your medicine list and insurance card ready. Say at the start if you are pregnant, have a weakened immune system or a serious long-term condition, or if you are calling about a baby or an older adult, because that changes the advice. Do not hang up without a clear plan, and call back or seek care again if symptoms change rather than waiting for the original advice to fit. None of these services are a substitute for 911 in a life-threatening emergency.

When to go to the ER

The hospital emergency room, or emergency department, is open around the clock for serious illness and injury. It is the right place for chest pain, trouble breathing, heavy bleeding, loss of consciousness, signs of stroke and severe injuries. It is usually the slowest and most expensive place for everything else, because patients are seen in order of medical need, a process called triage, rather than in order of arrival.

For a suspected heart attack or stroke, call 911 rather than driving, because paramedics can start treatment on the way and alert the hospital. When you arrive at the ER, tell the triage nurse clearly what the worst symptom is and when it started, rather than the whole history. Bring a list of your medicines, or the bottles, and your insurance card. Avoid eating or drinking until you have been assessed, in case you need a procedure.

The ER is not the place for prescription refills, work notes or long-standing problems that have not changed, all of which your doctor's office or a telehealth visit can usually handle. After any ER visit, follow up with your own doctor, who may not automatically be told what happened. Ask the ER for a copy of your discharge instructions and any test results to take with you.

Your rights in the ER

Under the federal Emergency Medical Treatment and Labor Act, hospitals with emergency departments that take part in Medicare must screen anyone with a possible emergency and stabilize them, regardless of insurance or ability to pay. The No Surprises Act also protects most insured people from surprise out-of-network bills for emergency care. In an emergency, go to the nearest ER rather than searching for an in-network one, and deal with billing questions later.

Referrals, prior authorization and appeals

A referral is a written order from your primary care doctor for you to see a specialist. HMO plans usually require one before they will pay for a specialist visit; many PPO plans do not. Prior authorization, sometimes called preauthorization, is approval from your insurer in advance for certain tests, procedures, medicines or equipment. Both exist because plans want primary care to coordinate care and want to check that expensive services are covered and appropriate before they are given.

Skipping a required step can leave you with the full bill, so ask your doctor's office whether a referral or prior authorization is needed and whether it has been sent. Keep a simple log: dates, reference numbers and the names of the people you speak to. Do not assume silence means approval, because requests do get lost. If your symptoms get worse while you wait, tell your doctor, since that can change the urgency, and an emergency never needs prior authorization.

After a claim is processed, your insurer sends an Explanation of Benefits (EOB) showing what was billed, what the plan paid and what you may owe. It is not a bill. Compare each bill from a provider with its EOB before paying, and ask about anything that does not match, such as a service you did not receive or an amount you owe that is higher than the EOB shows.

If you are denied

If your plan denies a request or a claim, you have the right to know why and to appeal. For most plans you have 180 days from the denial notice to file an internal appeal, in which the plan reviews its own decision. If that fails, you can ask for an independent external review, generally within 4 months of the final internal denial; the reviewer's decision is binding on the plan. For urgent situations, ask for an expedited review, which is decided much faster, and ask your doctor to send a letter explaining why the service is needed.

Second opinions

Asking another clinician to review a diagnosis or treatment plan is common, especially before major surgery or cancer treatment, and most doctors expect and support it. Ask your current doctor for names, say specifically what you want reviewed, and request copies of records and scans so tests need not be repeated. Medicare Part B covers a second opinion before surgery that is not an emergency, and a third if the first two differ. Many private plans cover second opinions too, though some require a referral. Do not stop current treatment while you wait unless you are told it is safe.

Having tests and scans

A blood test usually takes under five minutes. Most of the preparation that matters depends on which test it is, so the instructions you are given override any general advice. Only some tests need fasting; fasting when you do not need to is unhelpful and can be risky if you have diabetes. Drinking water beforehand, unless told otherwise, makes veins easier to find. Say if you have fainted at a blood test before so you can lie down, and tell the staff if you take blood thinners or have a bleeding disorder.

Results often arrive within a few days, and they may appear in your patient portal before your doctor has reviewed them. A value slightly outside the reference range is common and often not significant, so wait for your doctor's interpretation rather than searching online in alarm. Equally, do not assume that no news means a normal result; ask how and when you will be told. Using an in-network lab keeps costs down.

An MRI scan uses a strong magnetic field and radio waves rather than X-rays, and takes roughly 15 to 90 minutes depending on the area scanned. Because the magnet is always on, safety screening matters. Tell the imaging center when you book about any pacemaker, implanted defibrillator, cochlear implant, aneurysm clip, other implant or metal fragment in your eyes, and complete the safety questionnaire every time, even if you have had a scan before.

Before an MRI

Leave jewelry, watches, hearing aids and cards with magnetic strips outside the scan room. The machine makes loud knocking noises, and earplugs or headphones are provided. If you find enclosed spaces difficult, say so beforehand so that medicine to help you relax, or an open scanner, can be discussed. Some scans use a gadolinium-based contrast dye injected into a vein; tell staff if you are or might be pregnant or have kidney problems. Many plans require prior authorization for an MRI, so confirm it and the facility's network status before the appointment.

Hospital stays and leaving the hospital

Discharge is the point at which hospital care ends and whatever comes next has to be arranged already. Most problems after a hospital stay involve medicines and follow-up, and both are settled in the hours before you leave. A good discharge plan covers which medicines have been stopped, started or changed and why, follow-up appointments, any equipment or home health care, and which symptoms mean you should get help.

Ask for these things in writing, including who is responsible for booking each follow-up appointment and who to call after hours. Do not restart old medicines at home that were deliberately stopped in the hospital, and do not assume that your primary care doctor already knows what happened. The hospital should send a discharge summary, but not always right away, so bring your copy to your next appointment.

If you have Medicare and think you are being discharged too soon, you can ask an independent reviewer to look at the decision; the hospital must give you a notice explaining these rights. Be aware of observation status too: you may be classed as an outpatient even if you stay overnight in a hospital bed, which affects what Medicare pays, including for any skilled nursing facility care afterward. Ask whether you are an inpatient or under observation.

Before a planned hospital stay

For planned surgery or a procedure, a little preparation prevents most surprises. Confirm that prior authorization has been granted and that the hospital, surgeon, anesthesiologist and any lab or imaging services are in your network. Ask what to stop or adjust beforehand, especially blood thinners and diabetes medicines, and when to stop eating and drinking. Arrange who will drive you home and who will help in the first days. Bring your medicine list, insurance card, and a copy of any advance directive, and ask the team to explain consent forms before you sign them.

Your health records and privacy

Under the HIPAA Privacy Rule, you have a legal right to see and get a copy of your medical and billing records held by doctors, hospitals and health plans. It is a right, not a favor. The provider must respond within 30 days of your request, with one 30-day extension allowed if they tell you why, and they may charge only a reasonable, cost-based fee for copies. An unpaid bill is not a valid reason to refuse access.

Start with your patient portal, which often shows recent results, visit notes and medicine lists. For anything more, ask the office that holds the record, such as your doctor's practice or the hospital's medical records department, and say which dates or departments you want and in what format, including electronic copies. You can also direct the provider to send your records to another doctor or to someone you choose.

Reading your record lets you check for mistakes, such as an allergy you do not have or a medicine you stopped years ago. You can ask in writing for errors to be amended; the original entry is usually not deleted, but your correction is added. If a request is refused or ignored past 30 days, complain to the provider first and then to the HHS Office for Civil Rights.

Who else can see your records

HIPAA also limits who can see your health information. Doctors, hospitals and plans can share it with each other for your treatment, for payment and for running their services without asking you each time, but most other uses, such as marketing, need your written permission. Every provider must give you a Notice of Privacy Practices explaining how it uses your information. If you want a family member or caregiver to be able to discuss your care with your doctors, tell the practice and sign any authorization form it uses.

Getting help from a pharmacy

Pharmacists are among the most accessible health professionals, and you do not need an appointment to ask for advice. They can help you choose an over-the-counter medicine for a minor illness, explain how and when to take a prescription, and check for interactions when you start something new. Ask for a private area if you would rather not talk at the counter.

Pharmacists give many recommended vaccines, such as flu and COVID-19 shots, for eligible ages. Naloxone, which reverses an opioid overdose, is available over the counter as a nasal spray. People with Medicare drug coverage who take several medicines for long-term conditions may be eligible for medication therapy management, a structured review of everything they take. What pharmacists can test for or prescribe varies by state, so ask what your local pharmacy offers.

Keep a single list of all your medicines, including supplements, and share it with your pharmacist. A common and avoidable mistake is taking the same active ingredient in two products at once, such as acetaminophen (Tylenol) on its own and again in a cold remedy. Using one pharmacy for all your prescriptions makes it easier for the pharmacist to spot problems. A good pharmacist will refer you to a doctor rather than suggest self-care if your symptoms suggest something more serious, or if they have gone on for weeks.

Special situations: children, older adults, caregivers and people without insurance

Children usually get primary care from a pediatrician or family medicine doctor, with regular well-child visits that most plans cover without a copay. Your pediatrician's after-hours line is often the best first call for a sick child at night, because the clinicians know which symptoms in children need urgent attention. If you are calling about a baby, say so at the start.

Older adults often juggle several specialists and many medicines, which raises the risk of gaps and interactions. Asking one doctor, usually the primary care provider, to keep an overview helps, as does bringing every medicine to a yearly review. If you help an older parent or a partner manage their care, ask them to sign a HIPAA authorization so their doctors can talk with you, and consider whether a health care power of attorney is appropriate.

If you have no insurance or very limited income, you still have options. Community health centers offer primary care, dental and mental health services on a sliding fee scale. Hospitals, especially nonprofit hospitals, have financial assistance policies that can reduce or cancel bills, and you can check whether you qualify for Medicaid, which you can apply for at any time of year. If you are uninsured or paying yourself, you have the right to a good faith estimate of costs before scheduled care.

A practical yearly plan

Using health services well is mostly about doing a few things before you need them. A yearly routine keeps your information current and means that when something goes wrong, you already know where to turn. It also catches the small administrative problems, such as an expired referral or a doctor who has left your network, before they turn into large bills.

Once a year, ideally around your plan's renewal, check that your primary care doctor and any regular specialists are still in network, book your checkup or Medicare Annual Wellness Visit, and review your medicine list with your doctor or pharmacist. Update the numbers saved in your phone and confirm your patient portal login still works. Keep your EOBs and medical bills in one folder for the year so that you can compare them and spot errors.

• Save your doctor's office and after-hours numbers, your insurer's nurse line and the nearest in-network urgent care
• Book a yearly checkup or Medicare Annual Wellness Visit and recommended screenings
• Bring an up-to-date list of every medicine and supplement to each appointment
• Check referral and prior authorization rules before booking specialists, tests or scans
• Compare every bill with its Explanation of Benefits before paying
• Download or request copies of important records, such as scan reports and discharge summaries
• Review whether your plan still covers your doctors and medicines before the next enrollment period

Every guide in this topic

• Finding a Primary Care Doctor: What the Evidence Actually Says
• What the Guidance Really Says About When to Go to the ER
• The Evidence on Using a Nurse Line or Urgent Care, Without the Hype
• Having an MRI Scan: What Published Guidance Supports
• Having a Blood Test: Sorting the Evidence From the Noise
• The Evidence on Getting a Referral and Prior Authorization, Without the Hype
• The Evidence on Asking for a Second Opinion, Without the Hype
• The Evidence on Leaving Hospital, Without the Hype
• Accessing Your Health Records: Sorting the Evidence From the Noise
• Getting Help From a Pharmacy: What the Evidence Actually Says

Frequently asked questions

Do I really need a primary care doctor if I am healthy?

Yes, it is worth having one. A regular doctor makes preventive care, prescriptions, referrals and follow-up much simpler, and many plans require you to name one. Finding a doctor while you are well avoids long waits for new-patient appointments when you are sick, and most plans cover a yearly checkup in network without a copay.

How do I decide between urgent care and the ER?

Use urgent care for problems that need same-day attention but are not life-threatening, such as sprains, minor cuts, earaches or urinary symptoms. Go to the ER, or call 911, for chest pain, trouble breathing, heavy bleeding, signs of stroke, severe injury or loss of consciousness. If you are unsure and it is not on the emergency list, call a nurse line first.

Is a telehealth visit as good as an in-person appointment?

For many minor illnesses, medicine questions, mental health care and follow-up visits, telehealth works well and is often cheaper and quicker. It cannot replace an exam when someone needs to listen to your chest, look in your ears or feel your abdomen, and the clinician will tell you if you need to be seen in person.

What is the difference between a referral and prior authorization?

A referral is your primary care doctor's order for you to see a specialist, which HMO plans usually require. Prior authorization is your insurer's advance approval for certain tests, procedures or medicines. A service can need one, both or neither, so ask your doctor's office and check your plan before booking.

My insurer denied a test my doctor ordered. What can I do?

Ask the plan for the reason in writing and ask your doctor's office whether they can supply more information. You can file an internal appeal, usually within 180 days of the denial notice, and if that fails, request an independent external review. For urgent cases, ask for an expedited review. Keep copies of every letter and note every call.

Will my doctor be offended if I ask for a second opinion?

Most doctors expect and support second opinions, particularly before major surgery or cancer treatment. Framing it as wanting to be sure, rather than a loss of confidence, keeps the conversation easy. Your current doctor can often suggest names and send your records, which is usually quicker than arranging everything yourself.

Should I fast before every blood test?

No. Only some tests need fasting, and your doctor or the lab will tell you if yours does. Fasting unnecessarily can make you feel faint and can be risky if you have diabetes. Unless told otherwise, drink water beforehand, which makes your veins easier to find.

What is observation status, and why does it matter?

You can stay overnight in a hospital bed and still be classed as an outpatient under observation rather than an admitted inpatient. For people with Medicare, this affects what you pay and whether Medicare covers skilled nursing facility care afterward. Ask the hospital staff directly whether you are an inpatient or under observation.

Can a doctor refuse to give me my records because I owe money?

No. Under HIPAA, an unpaid bill is not a valid reason to deny you access to your own records. Providers must respond within 30 days, with one 30-day extension if they explain why, and can charge only a reasonable, cost-based fee. If you are refused, complain to the provider and then to the HHS Office for Civil Rights.

What can a pharmacist help with besides filling prescriptions?

Pharmacists can help you choose over-the-counter medicines, check for interactions, explain how to take a medicine, and give many recommended vaccines. Naloxone for opioid overdose is available over the counter. Medicare drug plans offer medication therapy management to eligible members. What pharmacists can test for or prescribe varies by state.

When to speak to a doctor

See your primary care doctor for new symptoms that last or keep coming back, and contact your doctor the same day if symptoms worsen sharply while you wait for a referral, approval or test result. After a hospital stay, call your doctor or the hospital unit promptly for fever, worsening pain, breathlessness, or redness and swelling at a wound or IV site. Call 911 for chest pain or pressure, signs of stroke, severe breathlessness, heavy bleeding, seizures or someone who is unresponsive; emergencies never need prior authorization and ERs must screen and stabilize you regardless of insurance. Call Poison Control at 1-800-222-1222 for a possible poisoning or medicine overdose, and call or text 988 in a mental health crisis.

Where this comes from

• HealthCare.gov — Primary care provider (PCP)
• Medicare.gov — Yearly "Wellness" visits
• American College of Emergency Physicians — Know When to Go
• HHS — What is telehealth?
• HealthCare.gov — Appealing a health plan decision
• Medicare.gov — Second surgical opinions
• Medicare.gov — Your discharge planning checklist
• HHS — Individuals' Right under HIPAA to Access their Health Information
• MedlinePlus — Blood Tests
• FDA — MRI (Magnetic Resonance Imaging)

How this page was put together

Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.

Medical disclaimer

This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.