It has been nearly 20 years since I officially practiced medicine, but my friends and family consider me their frontline medical adviser. In an age when it is hard to get a doctor on the phone and can be pricey to see one, I remain really good at screening symptoms. The vast majority of the time, I can assure people that their anxiety is unfounded. Of course, every once in a while, my advice is “Yikes, worry more!” Here are some common medical worries you can set aside—along with a little guidance on when you should indulge them.

Don’t worry about: A single elevated blood-pressure reading

The human body is constantly changing in response to an array of factors: stress, medications, what you eat, how you sleep. This is definitely true of blood pressure, particularly the top number in the blood-pressure measurement, the systolic blood pressure. In fact, there is a phenomenon called “white coat hypertension,” in which blood pressure goes up when the measurement is taken at the doctor’s office because you’re nervous about having it checked! A friend of mine was recently in the hospital, hooked up to a display that checked his blood pressure every 15 minutes, with tremendous variation. It nearly drove him crazy.

When to worry: If you get a high reading several times in a month, talk to your doctor; untreated high blood pressure can lead to heart disease and stroke. Extremely elevated blood pressure (systolic pressure over 180 or diastolic pressure over 110) is a medical emergency.

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Don’t worry about: A blood-test result that’s a little high or low

Even if the lab report says the number is out of normal range, that value is most likely normal for you. For his entire life, my husband has had a slightly low platelet count, but he has never had bleeding problems (platelets help with clot formation). No problem, no disease. Part of the reason a new doctor does routine blood work when you’re feeling good is so that she can learn what is typical for you.

Don’t worry about: Low blood pressure

You know the saying “You can never be too rich or too thin”? Low blood pressure is kind of like that. It puts less stress on your organs, so it’s generally considered a good thing.

When to worry: If low blood pressure leaves you feeling lightheaded or faint, or if you feel your heart fluttering, then you need to see a doctor.

Don’t worry about: A couple days of nausea, vomiting or diarrhea

People want to know if it’s food poisoning or a virus, but in terms of healing, it doesn’t really matter. If there is no intense abdominal pain, high fever or blood in your stool, your body will take care of it. The important thing is not to get dehydrated. I prefer that old favorite, flat ginger ale, but any clear liquid, like water or Gatorade, will do.

When to worry: If you feel faint or are vomiting up blood, get to the doctor.

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Don’t worry about: Painless lumps

As bodies age, they develop a wide variety of lumps. The overwhelming majority of them are not cancerous. The causes of lumps are so numerous that it is impossible to give a complete list here, but they range from benign cysts to fatty deposits under the skin (called lipomas). Make sure you show them to your doctor on your next visit, but try not to be too alarmed.

When to worry: Some lumps should be evaluated as soon as possible. Breast lumps should never be ignored. Lumps that are tender, warm and red could be from underlying infections that need treatment. Hard or fast-growing lumps should also be seen promptly.

Don’t worry about: Bleeding

In terms of species survival, it’s probably good that the sight of blood provokes panic. But most of us panic more than we should. Cuts on certain parts of the body, like the scalp, can bleed profusely, but that shouldn’t necessarily cause alarm. Put pressure on a cut for 5 to 10 minutes to see if you can get it to stop bleeding. If you can’t, or if the two sides of the slice seem widely separated, you may need stitches to help healing.

When to worry: If you’re not sure whether a cut needs stitches, it’s not wise to wait and see. Wounds need to be stitched within 24 hours or the risk of infection rises markedly.

Don’t worry about: A little rectal bleeding

The most embarrassed call I receive concerns blood on toilet paper or in the bowl. It is almost always related to hemorrhoids or small cuts in the rectal area rather than a sign of an ulcer or cancer. Try taking a stool softener, or eat more fruits and vegetables to do the same trick.

When to worry: If the bleeding persists for more than two or three days or is painful, head to the doctor.

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Don’t worry about: Sharp, localized chest pain

We tend to associate the chest with the heart, but there are lungs, bones, muscles and digestive organs in there, too. Sometimes chest pain that’s worse with a cough, a deep breath or movements of the torso, like lifting or twisting, can be caused by strains or irritation in the small muscles and ligaments that surround the ribs. These can be due to injury or a viral infection and generally resolve themselves; a nonsteroidal medicine like ibuprofen may help in the meantime.

When to worry: If you are also short of breath or have a fever, see a doctor. In that case, sharp, localized pain could be a sign of a lung problem. And if you have any doubt about whether you should get medical help for chest pain, it’s always better to err on the side of caution.

Don’t worry about: Rashes

During my medical training, I had an itchy rash on my arms and legs. It lasted two weeks and went away. I still have no idea what it was. Minor rashes are part of life, and no cause will be found for many of them. Use common sense to treat symptoms—taking an antihistamine or applying hydrocortisone cream can help with itching, for example—and think about new products or foods you’ve come in contact with so you can try to avoid a recurrence. Have you used any new shampoos? Is the rash only on the legs (in that case, think plant allergy)? Only on areas exposed to the sun? Only on areas under clothing?

When to worry: If an itchy rash comes on suddenly while taking a medicine (particularly an antibiotic) or eating a new food, seek immediate medical attention, especially if you also have shortness of breath or difficulty swallowing. It could be the start of a life-threatening allergic reaction. Also, if the itching is unbearable despite over-the-counter treatment, you might need something stronger, like a short course of steroids.

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Should you worry more?

As I said, usually my advice involves calming unneeded anxiety. Most of my friends are worriers. But there is another type of patient—the denier—and those people should worry more. That group would include my own husband. So if you’re one of them, here are a few things that should always prompt an urgent medical visit: chest pain or pressure that you can’t localize with one finger and comes back every time you exercise; the worst headache of your life; intense abdominal pain, particularly if accompanied by fever; and shortness of breath severe enough that you have trouble finishing a sentence. This list is by no means complete, but these symptoms should set off immediate alarms. Put down this magazine and see a real doctor!

Elisabeth Rosenthal is a correspondent for The New York Times and a graduate of Harvard Medical School.

This article originally appeared on Health.com.

Contact us at letters@time.com.