10 Things You Should Never Do Before a Doctor Appointment—and 4 Things You Should

Updated: Jul. 09, 2024

Whether you're going in for checkups or common tests, here's how to get the most out of your next visit.

red coffee cup. top view
Dima Sobko/Shutterstock

Don’t drink coffee before a blood pressure test

Your blood pressure will be probably be taken at a checkup, so avoid coffee right before your appointment: it could affect the results. “Using coffee or other caffeine such as energy drinks or colas within an hour of having your blood pressure measured can make the number artificially higher,” says James Dewar, MD, vice chairman of family medicine at the University of Pittsburgh Medical Center (UPMC). “The same goes for tobacco products and over-the-counter decongestant medications.” Don’t miss everything you should know about coffee and high blood pressure.

Get The Healthy @Reader’s Digest newsletter

Bacon slices on a tray
Y Photo Studio/Shutterstock

Don’t eat a high-fat meal before getting blood drawn

You should also skip the fettucini alfredo before a regular blood workup. “If you wouldn’t normally have a high-fat meal, then don’t do it, so your physician can get an accurate picture of your health,” says Deepa Iyengar, MD, associate professor of family and community medicine at McGovern Medical School at UTHealth and an attending physician at Memorial Hermann-Texas Medical Center. Unusually large meals could skew test results. In fact, you may need to avoid eating in general. “If your blood work will include a measurement of cholesterol or other fats, it is best to avoid any calories for eight to ten hours before the test is drawn,” says Dr. Dewar. “Your blood sugar and certain fats in the blood called triglycerides can be increased for a bit after you eat.” And you may not have a choice: you’ll probably be told to fast and only drink water before a regular blood workup, says Dr. Iyengar.

Doctors Reveal the Real Questions You Should Be Asking Them

Close-up Of A Woman's Hand Drinking Glass Of Water

Do drink lots of water before a physical

In general, it’s a good idea to hydrate before seeing the doc for a checkup. “Being well hydrated at the time of a physical will make your pulse and blood pressure at their best,” Dr. Dewar says. “If you are having blood work or urine testing done, being mildly dehydrated can cause artificial abnormalities in the testing that can confuse the results.” You do want the doctor to picture your normal lifestyle, but you should be drinking lots of water anyways.

Here’s How Much Water You Really Need in a Day, with Nutritional Scientists’ Latest Wisdom

close up of woman holding plate with avocado toast as fresh snack, day light.
Andrej Rutar/Shutterstock

Do eat as you normally would before a checkup

You don’t need to change your eating habits before an annual appointment, even if you want to seem healthy. “Your providers would like you to be honest and upfront about your lifestyle and diet so they can have an accurate history of your health and provide you with the best possible care,” says Gregory John Galbreath, MD, a PIH Health physician in Whittier, CA. After all, a few days of healthier eating probably won’t matter. “It takes a long time for a diet to change cholesterol and blood sugar, so a dietary change of a few days or meals isn’t going to do much,” Dr. Dewar says. Changes occur over the long term, so just eat healthy as often as you can.

10 Secrets to Finding a Doctor You Can Trust

healthcare, treatment and medicine concept - bottle of medication or antipyretic syrup and spoon
Syda Productions/Shutterstock

Don’t take cold medicine before a sick visit (if you can)

When you’re sick, your doctor may want to evaluate your symptoms without the effects of any over-the-counter medications. “If possible, don’t take anything so your doctor can see any abnormal findings and assess your condition,” says Dr. Iyengar. “Some medications may raise blood pressure, and your physician would not know if the medication or the illness could be the cause.” If you’re really hurting, it’s probably okay to go ahead—your doctor wants you to feel better. Just be ready to describe your symptoms. And definitely tell the doctor what you’ve taken. “If you are taking medications to help with an acute illness, it’s important to let the doctor know if they are helping and/or causing side effects,” Dr. Dewar says. “This can help the doctor and you decide on the next steps in treatment.”

Top view of a woman doing a manicure and paint nails with red lacquer

Don’t get a mani-pedi before the dermatologist

Dermatologists look at your whole body, including your nails, so keep them polish-free. “Avoid wearing nail polish or acrylic nails,” says Sarina Elmariah, MD, PhD, a dermatologist at Massachusetts General Hospital in Boston. Subtle clues in your nails can indicate bigger health problems, like anemia, diabetes, and even heart ailments. Plus, bare nails make it easy to spot fungus. Also, skip the cover-up and eye shadow, so your doctor can easily spot facial skin problems. “Avoid wearing makeup or be willing to remove it if necessary,” she says. But it is okay to wear sunscreen or lotions, she says.

Doctors Reveal the Annoying Things They Wish You Wouldn’t Do

Close-up of two men clink glasses of whiskey drink alcoholic beverage together while at bar counter in the pub

Don’t drink alcohol before a cholesterol test

Avoid anything that alters your triglycerides (one of the four components measured in a cholesterol profile), since that could lead to needlessly worrying results. “The precaution to abstain 24 hours prior to a cholesterol test is based on the potential increase in triglycerides that could result soon after drinking alcohol,” says Joon Sup Lee, MD, chief of cardiology at the University of Pittsburgh School of Medicine and co-director of the UPMC Heart and Vascular Institute. You should also avoid sweets, high-fat foods and generally overeating before the test. “All of these in large quantities can affect the triglycerides in the short term,” Dr. Lee says. “Since we want the result of the cholesterol exam to reflect what your body is doing in the long term, it is best to avoid these short-term fluctuations.” Interestingly, Dr. Lee says regularly consuming one or two alcoholic drinks per day can actually have a mild beneficial effect on cholesterol levels. So go ahead and imbibe moderately when you’re not about to take the test.

Drinking This Much Alcohol a Week Can Negatively Affect Your Brain

Cup of tea on a wooden background top view.
Summer Photographer/Shutterstock

Don’t have caffeine before some stress tests

A stress test works your heart by walking on a treadmill or riding a stationary bike, for example, to see how it reacts and to ensure that it’s healthy. But if you’re having a  stress test that involves pharmacological agents, don’t have caffeine beforehand. “Caffeine counteracts the medicine—adenosine or regadenosine—used to simulate stress in the ‘chemical’ stress test,” says Dr. Lee.

Pair of dumbbells with blue yoga mat on wood floor,flare light

Don’t get too thirsty before a urine test

If you need to go for a urine test, don’t get dehydrated before your appointment. If you exercise, that means you need to drink plenty of water afterward. “Avoid episodes of major dehydration that can significantly alter a urinalysis,” Benjamin Davies, MD, chief of urology at the UPMC Shadyside/Hillman Cancer Center. “And avoid exercise that’s not in your normal daily routine.” If you exercise regularly, you probably know how your body will react and how to take care of it afterward. If you’re not used to it, you’re more likely to get dehydrated.

Here’s How Much Liquid Your Bladder Can Actually Hold, a Urologist Reveals

Doctor (gynecologist or psychiatrist) consulting and diagnostic examining woman patient's health in medical clinic or hospital healthcare service center

Don’t cancel your gyno if you have your period

“I would often joke with a patient who comes in and says, ‘Oh, I just got my period this morning, I’m so nervous,’ and it will be like right after I’ve done a cesarean section or delivery—like I never saw blood before!” says Mary Jane Minkin, MD, an OBGYN at Yale-New Haven Hospital and founder of the women’s health website MadameOvary.com.

Any tests you have with your period should be fine.

“The liquid Pap smear tests that are the standard now can be done even when a woman is menstruating, so no need to reschedule,” says Elizabeth Roth, MD, an ob-gyn at Massachusetts General Hospital. “Some women feel more comfortable rescheduling when they have their period, but medically there is no need to do this.” The only exception? If you’re going in for a specific concern, like funky discharge or a lesion, your period might obscure the exam. “But even that is not an absolute as we can still do vaginal cultures,” Dr. Roth says.

Africa Studio/Shutterstock

Don’t use deodorant before a mammogram

As if mammograms weren’t nerve-wracking enough, you can’t even protect against sweating! “Mammography advises women to skip deodorant/antiperspirant or powders on the day of the mammogram,” Dr. Roth says. “The reason is that many deodorants and powders contain aluminum, which on mammography looks similar to breast calcifications and could be read as a false positive.” You might be worried about  B.O., but the techs are used to it. Just shower beforehand and it won’t be that bad. Plus, it’s better than getting incorrect bad news later!

16 Clear Signs You Need to Fire Your Doctor

Close up of cherries

Don’t eat red food before a colonoscopy

Red or purple food can color your colon. Even those ice pops you’re advised to have while eating lightly the day before the test could be trouble. “We ask that these are not purple or red in color because they will mask the lining of the colon and could then affect the outcome of the study,” says Randall Brand, MD, a gastroenterologist at UPMC. Interestingly, iron supplements can have the same effect. And they can have some other not-so-pleasant consequences. “Iron can also stain the walls of the colon, again having an effect on a successful study,” Dr. Brand says. “In addition, iron, for many people, can be constipating and may make it difficult for the pre-colonoscopy laxatives to completely clean out the colon for a successful study.” You should stop taking iron a week before your colonoscopy. Other things that can be hard to clean out are high-fiber foods like raw fruits and vegetables, corn and beans. Dr. Brand says to avoid them for three days before the procedure.

Happy Couple in Cuddling in Bed
Megan Betteridge/Shutterstock

Do go ahead and have sex before the gyno or urologist

Don’t worry: doctors say it’s ok to do the deed before your visit, even though you may think that having sex before a visit to the gynecologist (for a woman) or the urologist (for a man) is a no-no. “Your doctor’s not going to yell at you for having sex—it’s totally fine,” Dr. Minkin says. But again, if you’re going to be nervous about it, skip the sex or reschedule. “It will not affect your physical exam either way, nor will it affect the Pap smear,” Dr. Roth says. For men, you might be worried that it will affect any tests you have on your urine, testicles, or prostate, but Dr. Davies says that’s not the case. “Normal sexual activity is fine,” he says. “There are no significant abnormalities associated with sexual relations.”

18 Truths People Will Tell Only Their Doctor

woman writing notes

Do write down your questions beforehand

No matter what kind of appointment you have, you may be nervous. After all, we can feel vulnerable and embarrassed during doctors exams. That’s why you should write down the things you want to talk about before you go (or even make a note on your phone). That way, you’re less likely to forget or lose your nerve. “It’s helpful if you come in with your list of questions so you’re not like, ‘Oh, I meant to ask this, I meant to ask that but I was too nervous,'” Dr. Minkin says. “Don’t be afraid to write down, ‘vaginal dryness is a problem’ if it is, and you can talk about it.” Other than that, the only other thing you should probably do is shower! Use these tips to get the most out of your next doctor visit.

Get The Healthy @Reader’s Digest newsletter for what’s trending in health and wellness daily. Follow us on FacebookInstagram, and Twitter, and keep reading: