Body temperature, without a thermometer?

Question

Even though I think everyone should have one, but some don't. So my question is, how can someone check their body temperature for a fever without using an oral thermometer? Is there a life hack for that?

I Do Not Have A Fever

Answer 1

No,

there is not a reliable hack to measure the body temperature in a sensible way.

We have to distinguish two case where an exact body temperature may matter:

1. Is there a rise in body temperature at all?
   We won't be able to tell whether a body temerature rose to more than 37.5 °C (99.5° F) - the lower limit of fever - without a thermometer measuring at 0.1° precision.
2. Is there a threatening rise in temperature?
   Fever greater than 41.5°C (106.7°F) usually comes from a serious unlerlying disease and may cause harm to our body. In this case we need to seek medical advice. We won't be able to tell without a thermometer if that was the case already.

But,

of course there a limited "hacks" that may tell us something is wrong, and we may have a fever.

1. Other people tell us we feel "warm".
   It is important to realise that we can not feel our own temperature, as our hands get warmer with the fever as well, and we can only feel a difference in temperature in relation to our skin temperature. With some experience we may be able to feel that somebody else hase an almost normal body temperature, may have fever above 39°C, or has a high fever above 40°C.
2. Our usual room temperature suddenly feels cold.
   Now this is very limited, but on a rising body temperature we subjectively feel cold, but as soon as the temperature falls we start to sweat. Therfore this will not tell us anything about our absolute temperature.
3. The heart beat rate may rise.
   According to the Liebermeister's rule the cardiac frequency rises by 8 to 10 beats per minute for every Celsius grade rise in body temperature. Obviously this rule is only applicable in case we rest, we do know our normal heart beat rate, and there is no other underlying cause of an altered cardiac frequency. The precision of this rule is more than doubtful.

So whenever we have the feeling that we may have a fever we should go and measure our body temperature with a medical thermometer. All else will not really tell us much more than what we already know: we may be ill today.

Answer 2

Materials

• Stopwatch
• Ice cubes of the same volume
• Measurement tool
• Silicone ice tray (or maybe a greased up plastic one)

Accuracy

This test will be highly inaccurate because of all of the environmental factors that interfere, so try to limit them as best you can. You will need a way to make sure ice cubes are going to have the same mass like a graduated syringe or tablespoon, a silicone ice tray to avoid chipping the cubes, and an AC unit would also help. Don't try to measure this way after eating. Don't do this test repeatedly. If anyone can think of any other factors that may interfere, please either edit this post to add them or comment with them.

Procedure

When you have a normal body temperature, take an ice cube and wait for the surface to become wet (so it is exactly at freezing temperature) and place it in your mouth. Without moving the ice cube around, measure how long it takes for it to disappear. This time will be your normal body temperature, so make sure to record it for later use. When you believe you have a fever, make a new set of ice cubes with the same mass. Don't try to store the same ice cubes for several days and think they're going to have the same mass. Measure how long it takes for you to melt the new ice cubes. If it takes less time, your body temperature is higher.

Safety

Keep in mind that you're putting ice in your mouth and keeping it in the same spot. Don't fill up your ice tray all the way, make the ice cube a small nugget to avoid freezer burn. Additionally, do not use this method as the way to get your temperature, use it as a fun experiment. You will have to make sure you don't have a dangerous fever with a real thermometer. You won't be able to get other peoples temperatures by comparing the time it takes for them to melt the ice cube with the time it takes for you to melt an ice cube.

Answer 3

I'm traveling, in a hotel, and febrile. I don't feel well enough to go buy a fever thermometer. I feel chilled and achy. I have had the heater on, every blanket on, for an hour. I assessed my neck temp with the back of my hand. I feel hot to myself. I left 80% of a steak dinner. I'm lethargic. My pulse is 75 at rest. Normally it's in the sixties. We were exposed to our grandson's snottiness nine days ago, and granddaughter's snottiness two days ago.

I'm diagnosing myself as febrile, most likely in the 100-102 *F range.

I'll test my theory by self administration of 600 mg ibuprofen. If my febrility declines, I was accurate in my assessment.

I'm a Professional Ski Patroller, Certified #580, accustomed to making do with limited resources

APP Preamble to our Code of Ethics

"We the willing, led by the unknowing, are doing the impossible for the ungrateful. We have done so much, for so long, with so little, we are now qualified to do anything with nothing."

Answer 4

You can put your lips against someone's forehead, if it is hot they are sick. If their forehead does not feel hot they do not have a fever.

If you are trying to feel your own temperature, your forehead may feel warm when you are normal temperature and vice versa.

Answer 5

I would recommend that you invest in a thermometer anyways. If you're confident that you do have a fever, though, a thermometer may be unnecessary. Do what you'd normally do for a fever, or go to a doctor. Or you could ask if someone will feel your forehead if you really would like to know, but can't get access to a thermometer.