Sometimes it can be hard to tell. And “going to the ER can be time-consuming and stressful,” says Kevin Biese, director of the division of geriatric emergency medicine at the University of North Carolina School of Medicine in Chapel Hill. But it’s always better to be safe than sorry, he says. The expert advice here can guide you on the steps to take in some key situations.

Call 911 immediately. For some problems, you want to get to an ER as fast as possible and by ambulance, according to Biese.

“If you call an ambulance, they can begin lifesaving care while you’re on the way to the emergency room,” he says. Plus, the emergency medical technicians in the ambulance can communicate with the hospital, so staff can be ready for you when you arrive. In some cases, EMTs can help determine where to take you for the best care.

For instance, if they suspect a stroke, they’ll take you to the nearest specialized stroke center. That’s because it’s important to receive clot-busting drugs within one to three hours after a stroke, according to the Centers for Disease Control and Prevention. (In some cases, it may be up to 4½ hours.) Below are some examples of when to call 911 right away.

• Chest pain.
• Shortness of breath (feeling breathless, gasping for air or, in severe cases, feeling as if you’re suffocating).
• Facial drooping on one side. This means that if you try to smile, it will be lopsided, according to Biese.
• Arm weakness on one side. If you raise both arms, one drifts downward.
• Speech difficulty. You’re unable to speak, or speech is slurred and unclear.
• A head injury followed by confusion, fainting or falling unconscious.
• Choking or a breathing stoppage.
• A spine or neck injury.
• A severe burn.
• A seizure.
• An electric shock or being struck by lightning.

Go to the ER. In the instances below, going to an emergency department is usually the right step. “Either have someone drive you or call 911,” says Saket Saxena, co-director of the geriatric emergency department at the Cleveland Clinic. You may also want to make your doctor’s office aware. Act if:

• You have respiratory symptoms (such as coughing, a runny nose or throat pain) plus shortness of breath. This could be a sign that you’re low on oxygen or you’re developing complications such as pneumonia, says Cameron Gettel, an assistant professor of emergency medicine at the Yale School of Medicine in New Haven, Conn.
• You fall and hit your head but are alert and/or think you may have broken a bone. (If you use blood-thinning meds, consider going to an ER after even a minor fall.) You’ll need to be evaluated for a concussion and internal bleeding, Biese says. If X-rays reveal a broken bone, timely care will ease pain and can prevent complications like permanent muscle damage.
• You have a deep cut that doesn’t stop bleeding after 10 minutes. While an urgent care clinic may be able to take care of a minor cut, a deep gash that may require stitches is best handled at an ER, Gettel says.
• You experience sudden, intense vomiting that lasts for more than an hour or two. You may need IV fluids. In addition, such vomiting can indicate a life-threatening condition, such as an intestinal blockage.

Call your regular doctor. In most other less obviously urgent — but uncomfortable — situations, such as a painful pulled muscle, first call your doctor’s office. Many primary care practices set aside time for people who need to be seen the same day, Saxena says.

If your regular doctor or another physician in the practice isn’t available, ask to see an advanced practice provider, such as a nurse practitioner or physician assistant, says Terry Fulmer, a registered nurse and president of the John A. Hartford Foundation in New York, which is dedicated to improving health care for older adults. They will have quick access to your medical records and may already be familiar with you.

If your provider’s practice is completely booked but is affiliated with a nearby medical center, check the center’s website to see whether it offers same-day appointments with other doctors in its system. Or consider looking for an opening with another local doctor on Zocdoc, Fulmer says. The online service searches for appointment slots filtering by medical specialty, location and insurance plan. “A lot of physician practices use it because it’s a way to fill last-minute cancellations,” she says.

On evenings and weekends, Saxena suggests phoning your doctor’s practice. There’s usually a provider on call who can advise you on whether you can wait to be seen when the practice reopens or if you need to go to an urgent care clinic or emergency room.

Consider urgent care. For illnesses and injuries that don’t have the potential to be life-threatening, urgent care clinics — which are often open in the evenings and on weekends — might be an option.

“If you tripped and think you sprained your ankle, and it’s after normal business hours, it makes sense to head to the urgent care clinic for an X-ray to make sure, and to get bandaged up,” Gettel says. The clinic can also, for instance, test for the flu and covid-19, check your heart rate and blood pressure, listen to your lungs, and, if you’re experiencing painful urination, check your urine and prescribe antibiotics if you have a urinary tract infection.

Urgent care facilities are usually run by doctors, nurse practitioners or physician assistants. “That’s different from an emergency room, which is staffed with board-certified emergency medicine physicians,” Biese says. “As a result, there may be a difference in experience and skill set.”

They’re best if your symptoms are straightforward. “Most urgent care centers don’t have the wide array of tests needed to try to figure a more complex situation out,” Biese says. And people with serious chronic health conditions, like heart failure, should probably go to an ER outside of their doctor’s office hours.

Another get-seen-fast possibility for simpler problems: pharmacy walk-in clinics at major retailers such as CVS, Target, Walgreens and Walmart, which may be open in the evenings and on weekends. These are a good option for ailments like strep throat, ear infections and urinary tract infections, Fulmer says. They can also treat minor sprains, cuts that don’t require stitches and rashes caused by poison ivy.

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