How To Use A Thermometer, According To A Family Physician

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A person holds up a thermometer while lying on the couch. If you're not quite sure how to use a ther...
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Adulting is hard. It's even harder when you realize that you feel feverish, that you need to take your temperature, and that, whoops, you don't even own a thermometer. If you're feeling feverish, or want to prepare for potentially getting sick, now might be a good time to admit you don't know how to use a thermometer.

Happily, it's really not all that difficult if you follow the directions on the packaging, says Dr. Michael Richardson, MD, a family medicine doctor with One Medical. "It’s always best to read the instructions for your thermometer before using it, as it will guide you on how to get the most accurate reading." This works great if you're buying a new thermometer, but what if you're fishing an old one out of the medicine cabinet in your roommate's bathroom?

As with other situations when you're going to touch your mouth or face, Dr. Richardson tells Bustle to make sure you wash your hands with soap and water before you use a thermometer, and you'll want to make sure the thermometer itself is clean, too. Rubbing alcohol followed by rinsing, or a thorough wash with cold water, should do the trick. This will "prevent the spread of any unwanted illnesses that may have been on it from the previous user," Dr. Richardson says, even if that previous user was you.

Try to keep your mouth closed for five minutes leading up to taking your temperature, and don't eat or drink anything in that window, either. You don't want to skew your results. Don't be tempted to leave the thermometer in your mouth wherever you feel like it; taking your temperature while holding it under your tongue is going to get you the most effective results.

Congratulations: you now know how to use a thermometer! But you probably still need to buy one. The Cleveland Clinic advises purchasing a digital thermometer for the most accurate readings.

Slight fluctuations above and below 98.6 degrees Fahrenheit are normal, but the Cleveland Clinic advises calling a doctor if your readings reach 100.4. Dr. Richardson also says it's important to consider your temperature in the context of any other symptoms you might have. "If you or your child does not have a temperature ([less than] 100.04F) but looks very ill, it is still a good idea to contact a health professional to see if any other steps need to be taken to feel better faster." And feeling better faster is really all anyone's looking to do nowadays.


Dr. Michael Richardson, MD, One Medical

Correction: A previous version of this article misattributed Dr. Richardson.

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