Things you should – and shouldn’t do – before your next doctor’s appointment

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 Dr James Dewar, 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.”

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You should also skip the fettuccini 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 Dr Deepa Iyengar, 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

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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 anyway.

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 Dr Gregory John Galbreath, a general practitioner. 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.

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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.”

Dermatologists look at your whole body, including your nails, so keep them polish-free. “Avoid wearing nail polish or acrylic nails,” says dermatologist Dr Sarina Elmariah. Subtle clues in your nails can indicate bigger health problems, like anaemia, 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.

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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 cardiologist Dr Joon Sup Lee. 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.

A stress test works your heart (by walking on a treadmill or riding a stationary bike) 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.

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,” urologist Dr Benjamin Davies. “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 afterwards. If you’re not used to it, you’re more likely to get dehydrated.

Although you might be grossed out by your period, your doctor’s seen worse. “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 caesarean section or delivery – like I never saw blood before!” says obstetrician/gynaecologist Mary Jane Minkin and founder of the women’s health website MadameOvary.com. But 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 obstetrician/gynaecologist Dr Elizabeth Roth. “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.

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