Why would my temperature be consistently high for weeks?

May 8, 2020 7:04 PM

Asking for friend: Normally my temperature tends to run a little low: 97.8-98.3 is typical. For the past two months, my temperature has been consistently around 99.5, about a degree and half above what is normal for me. What would cause that?

I have a couple of long term, chronic health problems but no new symptoms that make me think I have a current infection. Blood tests taken shortly after this started were normal. Is this my new normal? Is there something I should ask my doctor to check out?

posted by metahawk to Health & Fitness (23 answers total)

Thermometer malfunction?
posted by bq at 7:54 PM on May 8, 2020 [3 favorites]

I'm fairly certain I had coronavirus in January (although I haven't been tested). It started with a 103 degree fever, a dry cough, and severe asthma - severe enough that I had to use a nebulizer during the whole time. After three days, my fever went down to 99.5 and stayed there for OVER THREE WEEKS. We weren't talking about coronavirus at the time, so I had no clue why I had a fever for so long. After three weeks, I got tired of staying home and just went back to my life. After two more days, I still had the 99.5. After a week, my temperature was back down to normal.

So, all this to say - I'd go get a COVID-19 test. I'd be willing to bet you have/had it, even if you had no other symptoms. There are a lot of people with this virus that are asymptomatic.
posted by summerstorm at 8:14 PM on May 8, 2020 [3 favorites]

Response by poster: More than one thermometer, so not a malfunction.
posted by metahawk at 9:41 PM on May 8, 2020

I believe that pregnancy can cause a rise in body temperature of around this amount.
posted by kinddieserzeit at 9:53 PM on May 8, 2020 [1 favorite]

Response by poster: Friend is female but hasn't engaged in any activity which could cause pregnancy in the past year. Could a change in birth control cause a similar rise?
posted by metahawk at 10:07 PM on May 8, 2020

Is it a fever with no other symptoms and you do feel sick? Or just an elevated temperature and you feel ok? I had the former for almost a year. DM me if you want to know the eventual cause, don’t feel like posting it.
posted by Pacrand at 10:32 PM on May 8, 2020

What about time of day? I had an abnormally high temperature and I realized I was doing it post tea drinking 😬

Body temperature also naturally runs warmer certain times of the day
posted by pando11 at 10:56 PM on May 8, 2020 [1 favorite]

Bacterial infection, e.g. candida ?
posted by armoir from antproof case at 10:57 PM on May 8, 2020 [1 favorite]

Best answer: The Mayo Clinic has a pretty good rundown about fevers and their various causes.

Although most people consider 98.6 F (37 C) normal, your body temperature can vary by a degree or more — from about 97 F (36.1 C) to 99 F (37.2 C) — and still be considered normal.

Fever or elevated body temperature might be caused by:

* A virus
* A bacterial infection
* Heat exhaustion
* Certain inflammatory conditions such as rheumatoid arthritis — inflammation of the lining of your joints (synovium)
* A malignant tumor
* Some medications, such as antibiotics and drugs used to treat high blood pressure or seizures
* Some immunizations, such as the diphtheria, tetanus and acellular pertussis (DTaP) or pneumococcal vaccine

My takeaway from that is that this probably is a "real" fever and not just a variation on normal. It is above 99.5 and additionally, she usually runs a bit cold so her current temperature is roughly the equivalent of 100.1 in a "normal" person.

As the article says, in adults a fever usually isn't a great concern unless it reaches 103 or above. Basic on that my take on the situation is it is not a flaming hot "must go to ER now" type situation by any means but it is just out of the ordinary enough and has been going on for long enough that it would likely be worthwhile to schedule another doctor appointment and have them run some more tests and--at a minimum--eliminate some of the rare but potentially nasty possible causes.

Also my guess is, a doctor is likely to take one approach to this if it's been going on for a week or two, but maybe more of a serious look at it if it has continued for a couple of months. It could be the new normal but you'd want to at least take a look at some of the potential causes and rule them in or out.

Keep in mind that with COVID many physicians are doing telemedicine appointments and though those have their downsides they have their upsides as well. It can be pretty easy to just get 10-15 minutes with a doctor and get some questions answered.
posted by flug at 11:10 PM on May 8, 2020

Get tested for c19
posted by Jacqueline at 12:19 AM on May 9, 2020 [2 favorites]

I am NOT a doctor, just an educated civilian. Persistent low-grade fever is definitely one of those things that easily merits a doctor visit, even if it's by telemedicine. There are a few things that could potentially be causing it, and it could be something either very minor or very easily treatable - but in either case it's well worth investigating, especially given your friend has other chronic conditions. Basically, it's a sign that some kind of inflammation or homeostatic disruption is happening in the body, but there are so many different things that could cause that and no way to distinguish them without a clinician's judgement and potentially further investigations.
posted by Acheman at 12:24 AM on May 9, 2020 [4 favorites]

Your temp can also rise after eating as your body metabolizes food.
posted by mochapickle at 4:20 AM on May 9, 2020

Could a change in birth control cause a similar rise?

p sure menopause can, but idk if it ever lasts weeks at a time?
posted by poffin boffin at 4:42 AM on May 9, 2020 [1 favorite]

Any changes in medications in general during this time period?
posted by XMLicious at 4:55 AM on May 9, 2020

Best answer: Persistent low-grade fever is a feature of my autoimmune condition (which doesn't meet the criteria for any known diagnosis but is severe enough to keep me on plaquenil for 17 years.)

However, a pathogenic disease like Covid is a much likelier cause. Time to talk to a doctor.
posted by workerant at 6:31 AM on May 9, 2020

I had this happen when a minor cavity in a molar went wild and turned into an infection. I made an appointment to get the cavity filled and noted a mild fever for a week or so, but the cavity didn't hurt until I woke up one morning with half my face swollen and ended up getting an emergency root canal.
posted by SeedStitch at 6:56 AM on May 9, 2020 [1 favorite]

Best answer: I run a low fever around 99.5 with seasonal allergies. Most of the time the low fever is my only allergy symptom.
posted by ilovewinter at 9:28 AM on May 9, 2020

When I had COVID, my temperature was similar or lower. The typical body temperature fluctuates from 97ish first thing in the morning to high 98 at night. What this raised temperature means depends on your other symptoms. Is this the only bodily anomaly you’re experiencing? Do you break out in sweats? Chills?
posted by kinoeye at 11:02 AM on May 9, 2020

You say your friend hasn’t engaged in any activity that could cause pregnancy in the past year but that they are on birth control—does that mean they’re having intercourse and using birth control, or not having intercourse but using birth control for other reasons?

I very recently had a similar body temperature experience (in addition to other symptoms) that turned out to be caused by an ectopic pregnancy that I had no idea about because I had been perfect with my birth control pills and hadn’t missed any periods.

If your friend has been having intercourse, they should be aware of this possibility and take a pregnancy test or two—mine went undetected for so long I needed emergency surgery (from which I am currently recovering) to remove the entire Fallopian tube. I truly would not wish that experience, especially with hospitals as they are now, on anyone and hope your friend is dealing with something much less urgent!
posted by cabbage raccoon at 2:05 PM on May 9, 2020

I've been running a low fever for the past month or so as well. I'd been feeling really tired and headachy for a lot of March but chalked it up to allergies and stress since I had no cough or other symptoms.

We actually had a malfunctioning thermometer (kept getting weirdly low readings like 95, 93) and replaced it in late March. We pulled the new thermometer out of the box and literally my first reading was 101. Since then it's been consistently 99.5 or so; it does vary throughout the day, and about once a week or so spikes back up above 100. I changed birth control pills in late March, so that could be related; I've also read that people on birth control pills typically have a higher body temperature to begin with. (I'm not really sure of my usual baseline, but I think it's usually been 98-something when I get vitals taken at dr appointments.)

ilovewinter's comment about seasonal allergies is quite possibly the case for me as well; that would also explain the headaches and tiredness (which coincided with grass pollen time where I am). I tend to get hives around this time of year, too, for the same reason. Never had much reason to check my temp regularly before now but I wouldn't be surprised if that's all connected.
posted by saramour at 5:10 PM on May 9, 2020

Response by poster: Just to clarify, one of the chronic issues is PCOS so she is on continuous birth control (via shots) to avoid ovarian cysts.

Consulting a doctor makes sense but there is a history of doctors being no help with this type of diffuse, unclear complaint so having some ideas about what it might be helps her ask the doctor better questions.
posted by metahawk at 6:37 PM on May 9, 2020

Is your friend absolutely sure she has no other symptoms which may seem just like random annoyances? For example, bowel movements suddenly being looser throughout the week, back or other muscle pain?

I had the same constant 100 degree fever for most of April. I did a telemedicine appointment with a nurse and he asked me about a lot of symptoms that never occured to me. I had lost my appetite (just thought it was stress from starting a new job and the lockdown happening), loose stools (I thought it was related to my new bland diet due to loss of appetite), and lower back pain that I initially assumed was from poor posture working at home.

The nurse immediately sent me for a Covid test.

Your friend should do the same. Having a persistent low grade fever is a big sign. Other symptoms may be going ignored if your friend isn't looking out for them.
posted by joan_holloway at 7:38 PM on May 9, 2020

Best answer: I’m an internist. As flug wrote, the causes are legion. Your friend’s temperature staying below 100 is questionably worth the trouble of searching very hard for a cause. It would be expensive and time-consuming but more importantly the many tests could easily yield some false positives.

I’d do a thorough history and exam, a few lab tests, perhaps a chest x-ray, but no more workup unless there were another symptom (involuntary weight loss being the most important).
posted by neuron at 10:45 PM on May 9, 2020