Fever Lower in Morning, Higher in Afternoon

Have you ever noticed that if you're sick and running a fever, it's usually higher in the afternoon? Here's a question for you nurses: why is this? Recently I came across a log that my husband and I kept for my doctor when I had an upper respiratory infection. I was down in bed over a holiday weekend -- yuck! My rectal temps in the morning were .5 to 1 degree lower in the morning than later in the afternoon.

I would think activity level rising during the normal day's routines would account for the higher temperatures being recorded. When resting or sleeping your activity level is at its lowest, including slower respiration, so lower temperatures at rest would make sense as well.

Just an added thought...well, another question. How high do you let a fever get before you start on Tylenol or another remedy?

When I had the URI my doctor's nurse said unless I was uncomfortable, I didn't necessarily need to take something -- but to call if my temp went above 102. I told her that I was coughing like crazy despite the med and that my husband was taking my temp rectally. I remember her saying, "It's good if you can let him do that -- you'll get an accurate reading."

That's perfectly normal, and has to do with your circadian rhythm, and changes in your metabolic rate throughout the day. If you monitored your basal rectal temp through the day, you'd see that, whether or not you had a fever.

The hypothalamus is funny like that. It secretes hormones 24/7 to regulate temp...and a lot of other functions. So think of it not like a clock which ticks exactly the same for twenty four hours, but like a thermostat, sending the message to the furnace in order to reheat or cool down. If that makes sense...other things the hypothalamus does causes a release of energy and muscle movement...which also produces heat. No idea why the time of day has anything to do with it, but it makes sense that if you sleep at night your heat would be up from all the energy you expended throughout the day....If that works....or helps.

Mine has been higher in the afternoon when I am sick

It seems to me that, even when you're not sick, your temperature will be higher in the afternoon. I supposed it's related to being active during the day. I also think that's why women should use basal temperatures taken first thing in the morning when monitoring their fertility cycle.

It seems to me that, even when you're not sick, your temperature will be higher in the afternoon. I supposed it's related to being active during the day. I also think that's why women should use basal temperatures taken first thing in the morning when monitoring their fertility cycle.

You only need to monitor your fertility cycle if you are trying to get pregnant and having difficulty doing so. Following formulas for ovulation and fertility doesn't always work because basal temperature doesn't always correspond to ovulation. Generally, most couples should just fuck with wild abandon and they will get pregnant. "Saving yourself" for your supposedly most fertile days will frequently cause you to miss your actual fertile period.

Mine seems a bit higher at night.

Just an opinion here: Though many loathe, and are very reluctant to discuss the practice of rectal temperature taking, I'd not want it any other way when taken. Have had it done often as an adult, and both male and female care givers, MDs, RNs and others in the medical field, when taking my rectal temperature, have expressed the fact that though not as common as in years past, it is still the preferred route for accuracy whether during an illness or wellness check-up or other procedure requiring a determined body temperature reading. There was a period when I would run a low body temperature and those readings were always obtained rectally. Again, accuracy was the issue for the readings.

When measuring basal temperature for ovulation, it doesn't matter if you take it orally or rectally--NOT ONE BIT.

The point is to take it the same way at the same time each day when you get out of bed so activity doesn't affect your temperature.

Vicki: If I was sick my mother would have me take my temperature morning and evening but say "it's normal it's higher in the evening". Because this evening temperature depends on activity during the day the most reliable (for things like ovulation) is when you've just woken up.

I pity the poor women who use temperature to have a child or not to have a child (e.g. for religious reasons prohibiting "artificial" contraception) - you wake up you're not quite up yet and you have to take your temperature and record it.

This is for Pecan and the other skeptics here. The most accurate temperature is a rectal one, either basal or clinical. Best time to take your basal temperature is when you are at rest, after a good night's sleep. (My AM rectal temp is 98.4F) I don't need your "Pity" for having to take my temperature, half-asleep. Every morning of my chart day, my husband used to roll me over, pull down my pajama pants, and insert the lubed basal thermometer. Then, he would shave and record the reading when he was done. Now, I have two beautiful children, daughter-24, and a son-17! It worked for me- twice!

For me, rectal temperature is always lower in the morning and higher in the evening . Most times 98.4 - rectal in the morning and 99.8 just before bedtime. When I am down with an illness, the rectal method provides the "True body temperature " It is never affected by things like oral readings can , like food or drink or mouth breathing when congested.

I haven't recently been ill I believe working in retail helps my immune system. Also I take isotonix vitamins that go straight too my blood. They are supposed to be good for my immune system when I remember to take them.

My younger sister recently had the viscous flu. She noticed higher fever in the afternoon. I suppose the morning is a better time to get a nap in since sick people need rest.

My rectal temperature is always lower in the morning and higher in the evening . Most times 98.2 rectal in the morning and 99.6 in the night.

Very true and never really noticed that till you mention it but it's very true

That's normal. When you wake up your metabolism is lower.

With that tail ramoarikika your temperature should be much Hotter. 😉