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Causes of low grade fever with no symptoms. Persistent Low Grade Fever: Causes and Treatments

What are the causes of persistent low grade fever without symptoms? Discover the reasons behind this medical condition and the available treatments.

Understanding Persistent Low Grade Fever

The normal human body temperature is around 98.6°F, but it can fluctuate throughout the day. A low grade fever is when the body temperature rises slightly, usually between 100.5°F and 102.2°F. A persistent low grade fever occurs when the body temperature remains in this range for more than 2 weeks.

A fever is commonly a result of the body’s attempt to fight off an infection or another illness. However, some cases of persistent low grade fever can be more challenging to diagnose and treat.

Symptoms of Persistent Low Grade Fever

Some people may hardly notice that they have a low grade fever, while others may experience various symptoms, including:

  • Feeling warm to the touch
  • Sweating
  • Chills
  • Shivering
  • Headaches
  • Muscle aches
  • Dehydration
  • A general feeling of being unwell

Causes of Persistent Low Grade Fever

Respiratory Infections

Respiratory infections, such as a cold or the flu, can cause a persistent low grade fever that lasts for as long as the body takes to fight off the infection. Other symptoms may include coughing, sneezing, a stuffy or runny nose, a sore throat, chills, general fatigue, and lack of appetite.

Urinary Tract Infections (UTIs)

A urinary tract infection (UTI) may also be the underlying cause of a low grade fever. In addition to the fever, the person may experience symptoms such as pain in the abdomen, a burning sensation while urinating, frequent urination, and dark urine. Most UTIs can be treated with antibiotics.

Other Infections

Almost any infection can cause a fever, as the body’s natural response to fight off foreign invaders. Other sources of infections that may cause a low grade fever include food poisoning, exposure to pathogens from livestock, tuberculosis, and meningitis.

Medications

Some medications can cause a low grade fever as a side effect. If the medication is the cause, the fever should go away quickly, typically within 72 hours, once the person stops taking the drug.

Stress

Chronic stress may also lead to a low grade fever, particularly in young women. Reducing stress levels may help resolve the fever in these cases.

Cancer

In rare cases, a persistent low grade fever with no known cause may be a sign of cancer, such as leukemia, Hodgkin disease, or non-Hodgkin lymphoma. Other symptoms of cancer may include persistent fatigue, weakness, headaches, infections, lack of appetite, excessive bruising or bleeding, unexplained weight loss, and enlarged lymph nodes.

Diagnosing and Treating Persistent Low Grade Fever

If the symptoms of a persistent low grade fever do not improve with rest and time, it is essential to seek medical attention. The doctor may perform various tests, such as blood work, imaging scans, or a biopsy, to determine the underlying cause and provide appropriate treatment.

The treatment for a persistent low grade fever will depend on the underlying cause. For infections, the doctor may prescribe antibiotics or antiviral medications. For stress-related fevers, stress reduction techniques, such as meditation or counseling, may be recommended. In the case of cancer, the treatment will depend on the specific type and stage of the disease.

Preventing Persistent Low Grade Fever

While it may not be possible to prevent all cases of persistent low grade fever, there are steps individuals can take to reduce their risk:

  • Practice good hygiene, such as regular handwashing, to prevent the spread of infections
  • Manage stress through healthy coping mechanisms, such as exercise, relaxation techniques, and social support
  • Maintain a balanced and nutritious diet to support the immune system
  • Speak with a healthcare provider about any persistent or concerning symptoms

Conclusion

Persistent low grade fever can be a frustrating and concerning health issue, but understanding the potential causes and seeking prompt medical attention can help individuals find the appropriate treatment and relief. By being proactive about their health and addressing any underlying conditions, individuals can take steps to manage persistent low grade fever and maintain their overall well-being.

Persistent low grade fever: Causes and treatments

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  • Fact-check all health claims: Do they align with the current body of scientific evidence?
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The normal human body temperature is about 98.6°F, but it fluctuates throughout the day. A low grade fever is when the body temperature rises slightly, usually between about 100.5°F and 102.2°F.

The fever is persistent when the body temperature stays in this range for more than 2 weeks.

A fever is commonly a result of the body trying to fight off an infection or another illness. However, some cases are more difficult to diagnose and treat.

Continue reading to learn more about the symptoms, causes, and treatment of a persistent low grade fever.

Share on PinterestIf the body is fighting off an infection, a person may experience a persistent low grade fever.

Some people may hardly notice that they have a low grade fever. However, others may experience various symptoms, including:

  • feeling warm to the touch
  • sweating
  • chills
  • shivering
  • headaches
  • muscle aches
  • dehydration
  • a general feeling of being unwell

A persistent low grade fever is typically a sign that the body is fighting off an infection or another health issue and has raised its temperature to help these efforts.

These underlying issues can include:

Respiratory infections

Respiratory infections can cause a persistent low grade fever. Some of the most common respiratory infections, such as a cold or the flu, may cause a low grade fever that lasts for as long as the body takes to fight off the infection.

Other symptoms that may indicate a respiratory infection include:

  • coughing
  • sneezing
  • a stuffy or runny nose
  • a sore throat
  • chills
  • general fatigue
  • lack of appetite

Many simple respiratory infections do not require treatment, and the symptoms will go away in time.

Urinary tract infections

A urinary tract infection (UTI) may also be the underlying cause of a low grade fever. A UTI is a bacterial infection that occurs when bacteria multiply anywhere in the urinary tract, which includes the bladder, urethra, kidneys, and ureters.

In addition to a low grade fever, the person may experience symptoms such as:

  • pain in the abdomen
  • a burning sensation while peeing
  • frequent urination
  • a constant urge to urinate
  • dark urine

Most UTIs are simple to treat with antibiotics. The doctor may analyze a urine sample to determine the precise type of bacteria causing the infection to ensure that they prescribe the right treatment.

Other infections

Share on PinterestA person should talk to their doctor if they experience any symptoms of infection alongside a fever.

Almost any infection can cause a fever. A fever is one of the body’s natural responses to foreign invaders. The body may keep its core temperature elevated while it is fighting off the infection.

Other sources of infections that may cause a low grade fever include:

  • food poisoning
  • exposure to pathogens from livestock
  • tuberculosis
  • meningitis

Anyone experiencing symptoms of infection alongside a fever should see a doctor if the symptoms do not improve with rest and time.

Medications

Some medications can cause many different side effects, which may include a low grade fever. People can check the information on side effects and interactions that comes in the packaging or seek advice from a pharmacist.

As the author of a 2018 review notes, if the medication is the cause, the fever should go away very quickly — typically within 72 hours — once the person stops taking the drug.

Stress

Chronic stress may cause a low grade fever. A research paper from 2015 notes that a fever due to stress is most common in young women.

Reducing stress levels may resolve the fever in these cases.

Cancer

In rare cases, a persistent low grade fever with no known cause may be a sign of cancer.

A persistent fever can be a symptom of leukemia, Hodgkin disease, or non-Hodgkin lymphoma.

The person may also experience other symptoms of cancer, including:

  • persistent fatigue
  • weakness
  • headaches
  • infections
  • lack of appetite
  • excessive bruising or bleeding
  • unexplained weight loss
  • enlarged lymph nodes
  • excessive sweating at night

Many of these symptoms are not unique to cancer, however.

Anyone who experiences these symptoms along with a low grade fever should see a doctor for a diagnosis.

Chronic disorders

Many other chronic disorders may cause symptoms such as a low grade fever, including:

  • thromboembolic disease
  • arthritis
  • lupus
  • gout
  • thyroiditis
  • serum sickness-like reactions
  • serotonin syndrome
  • neuroleptic malignant syndrome

Diagnosing a persistent low grade fever may involve several different tests to eliminate potential causes.

The doctor will generally carry out a physical examination and question the person regarding additional symptoms and whether they have any chronic conditions.

The doctor may also ask about any medications that the person takes so that they can eliminate them as a cause of the fever.

They may order blood tests, such as a complete blood count (CBC), to get an overview of the person’s health. The results may help them decide which other tests, if any, they need to order.

If the doctor suspects that the person has a UTI, they may ask them for a sample of their urine to test.

Share on PinterestOTC drugs may help treat a low grade fever at home.

Treatment for a persistent low grade fever will depend on the cause. For instance, minor infections may not need treatment at all, whereas issues such as cancer require extensive treatment.

To alleviate the symptoms of a low grade fever at home, a person can try over-the-counter (OTC) drugs, such as ibuprofen (Advil) or acetaminophen (Tylenol).

A fever can cause dehydration, so it is vital to drink plenty of water.

It is important to treat a low grade fever in children, who may be more sensitive to temperature changes. Using children’s versions of OTC drugs may help control the fever while waiting to see a doctor.

A persistent low grade fever is a sign of an underlying issue, such as a mild infection or chronic condition. The fever may persist while the person is fighting off the infection.

For the most part, persistent low grade fevers are not a cause for concern. However, it is important to monitor the fever to see whether it gets worse.

Anyone who is concerned about their symptoms or experiences a persistent low grade fever for more than 10 days should see a doctor.

SHOP FOR OTC DRUGS

The drugs listed in this article are available online:

  • Ibuprofen
  • Acetaminophen

Persistent low grade fever: Causes and treatments

We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission Here’s our process.

Medical News Today only shows you brands and products that we stand behind.

Our team thoroughly researches and evaluates the recommendations we make on our site. To establish that the product manufacturers addressed safety and efficacy standards, we:

  • Evaluate ingredients and composition: Do they have the potential to cause harm?
  • Fact-check all health claims: Do they align with the current body of scientific evidence?
  • Assess the brand: Does it operate with integrity and adhere to industry best practices?

We do the research so you can find trusted products for your health and wellness.

Read more about our vetting process.

Was this helpful?

The normal human body temperature is about 98.6°F, but it fluctuates throughout the day. A low grade fever is when the body temperature rises slightly, usually between about 100.5°F and 102.2°F.

The fever is persistent when the body temperature stays in this range for more than 2 weeks.

A fever is commonly a result of the body trying to fight off an infection or another illness. However, some cases are more difficult to diagnose and treat.

Continue reading to learn more about the symptoms, causes, and treatment of a persistent low grade fever.

Share on PinterestIf the body is fighting off an infection, a person may experience a persistent low grade fever.

Some people may hardly notice that they have a low grade fever. However, others may experience various symptoms, including:

  • feeling warm to the touch
  • sweating
  • chills
  • shivering
  • headaches
  • muscle aches
  • dehydration
  • a general feeling of being unwell

A persistent low grade fever is typically a sign that the body is fighting off an infection or another health issue and has raised its temperature to help these efforts.

These underlying issues can include:

Respiratory infections

Respiratory infections can cause a persistent low grade fever. Some of the most common respiratory infections, such as a cold or the flu, may cause a low grade fever that lasts for as long as the body takes to fight off the infection.

Other symptoms that may indicate a respiratory infection include:

  • coughing
  • sneezing
  • a stuffy or runny nose
  • a sore throat
  • chills
  • general fatigue
  • lack of appetite

Many simple respiratory infections do not require treatment, and the symptoms will go away in time.

Urinary tract infections

A urinary tract infection (UTI) may also be the underlying cause of a low grade fever. A UTI is a bacterial infection that occurs when bacteria multiply anywhere in the urinary tract, which includes the bladder, urethra, kidneys, and ureters.

In addition to a low grade fever, the person may experience symptoms such as:

  • pain in the abdomen
  • a burning sensation while peeing
  • frequent urination
  • a constant urge to urinate
  • dark urine

Most UTIs are simple to treat with antibiotics. The doctor may analyze a urine sample to determine the precise type of bacteria causing the infection to ensure that they prescribe the right treatment.

Other infections

Share on PinterestA person should talk to their doctor if they experience any symptoms of infection alongside a fever.

Almost any infection can cause a fever. A fever is one of the body’s natural responses to foreign invaders. The body may keep its core temperature elevated while it is fighting off the infection.

Other sources of infections that may cause a low grade fever include:

  • food poisoning
  • exposure to pathogens from livestock
  • tuberculosis
  • meningitis

Anyone experiencing symptoms of infection alongside a fever should see a doctor if the symptoms do not improve with rest and time.

Medications

Some medications can cause many different side effects, which may include a low grade fever. People can check the information on side effects and interactions that comes in the packaging or seek advice from a pharmacist.

As the author of a 2018 review notes, if the medication is the cause, the fever should go away very quickly — typically within 72 hours — once the person stops taking the drug.

Stress

Chronic stress may cause a low grade fever. A research paper from 2015 notes that a fever due to stress is most common in young women.

Reducing stress levels may resolve the fever in these cases.

Cancer

In rare cases, a persistent low grade fever with no known cause may be a sign of cancer.

A persistent fever can be a symptom of leukemia, Hodgkin disease, or non-Hodgkin lymphoma.

The person may also experience other symptoms of cancer, including:

  • persistent fatigue
  • weakness
  • headaches
  • infections
  • lack of appetite
  • excessive bruising or bleeding
  • unexplained weight loss
  • enlarged lymph nodes
  • excessive sweating at night

Many of these symptoms are not unique to cancer, however.

Anyone who experiences these symptoms along with a low grade fever should see a doctor for a diagnosis.

Chronic disorders

Many other chronic disorders may cause symptoms such as a low grade fever, including:

  • thromboembolic disease
  • arthritis
  • lupus
  • gout
  • thyroiditis
  • serum sickness-like reactions
  • serotonin syndrome
  • neuroleptic malignant syndrome

Diagnosing a persistent low grade fever may involve several different tests to eliminate potential causes.

The doctor will generally carry out a physical examination and question the person regarding additional symptoms and whether they have any chronic conditions.

The doctor may also ask about any medications that the person takes so that they can eliminate them as a cause of the fever.

They may order blood tests, such as a complete blood count (CBC), to get an overview of the person’s health. The results may help them decide which other tests, if any, they need to order.

If the doctor suspects that the person has a UTI, they may ask them for a sample of their urine to test.

Share on PinterestOTC drugs may help treat a low grade fever at home.

Treatment for a persistent low grade fever will depend on the cause. For instance, minor infections may not need treatment at all, whereas issues such as cancer require extensive treatment.

To alleviate the symptoms of a low grade fever at home, a person can try over-the-counter (OTC) drugs, such as ibuprofen (Advil) or acetaminophen (Tylenol).

A fever can cause dehydration, so it is vital to drink plenty of water.

It is important to treat a low grade fever in children, who may be more sensitive to temperature changes. Using children’s versions of OTC drugs may help control the fever while waiting to see a doctor.

A persistent low grade fever is a sign of an underlying issue, such as a mild infection or chronic condition. The fever may persist while the person is fighting off the infection.

For the most part, persistent low grade fevers are not a cause for concern. However, it is important to monitor the fever to see whether it gets worse.

Anyone who is concerned about their symptoms or experiences a persistent low grade fever for more than 10 days should see a doctor.

SHOP FOR OTC DRUGS

The drugs listed in this article are available online:

  • Ibuprofen
  • Acetaminophen

causes and what is subfebrile temperature If the deviation on the temperature scale exceeds 0.5 ° C, in one direction or the other, this is not a critical indicator.

However, if the body temperature systematically rises to 37.1°C for no apparent reason, this is a reason to go to the doctor for a detailed clarification of the circumstances.


Usually, subfebrile temperature is called when the mark on the thermometer rises to 38 ° C and stays at this border. And often this is a temperature of 37.1 ° C.

In fact, an increase in body temperature does not occur from scratch.

The leading therapist of the R + Medical Network private clinic will tell you how to recognize subfebrile temperature and what are the most common reasons for this in medical practice.


Despite the fact that the causes of low-grade fever can be very different. Our doctors will still try to detail and convey the most important information to you so that you can pay attention to the hidden symptoms of the pathology in a timely manner and seek medical help. Usually, subfebrile temperature is called when the mark on the thermometer rises to 38 ° C and stays at this border. And often this is a temperature of 37.1 ° C.

What is subfebrile temperature?

Being informed is important. Especially when it comes to your own well-being or the health of loved ones.

So, body temperature can change throughout the day, depending on how you feel, climatic conditions, time of day. Therefore, deviations in the temperature regime of 0.5-1°C are not considered a pathology.


Therefore, if the temperature of 37.1°C lasts for a long period, then it returns to normal, and then rises again – sign up for a consultation with a specialist. Since the real problem can be detected only after a thorough diagnosis of the body.

Causes of subfebrile temperature can be identified using a complete blood count, fluorography, ultrasound, MRI, etc. Therefore, if the temperature of 37.1 ° C lasts for a long period, then returns to normal, and then rises again – sign up for a consultation with specialist. Since the real problem can be detected only after a thorough diagnosis of the body.

An increase in temperature is most often an immune reaction to an inflammatory process in the body or an infection.

Thus, the immune system is actively involved in the fight against the “enemy” and signals that a failure has occurred. A virus or a focus of the inflammatory process has appeared in the body.


Therefore, it is very important not to delay the visit to the doctor, but to do it as soon as possible at the first signs of the disease. After all, any disease is always easier to prevent than to treat in the last stages of pathology.

The main causes of subfebrile temperature

The most common reasons why the body can give temperature alarms are:

  1. Anemia.
  2. Intestinal parasites
  3. Tuberculosis.
  4. AIDS/HIV.
  5. Toxoplasmosis, sepsis.
  6. Oncological diseases.
  7. Diseases of the thyroid gland.
  8. Viral hepatitis, intestinal infection.
  9. Autoimmune diseases (allergies, arthritis, ulcerative colitis, rheumatism).
  10. Hormonal disorders (in pregnant women, as a variant of the norm).

By the way, the causes of a temperature of 37 ° C in women may well lie in the natural ovulation period, so if you are approaching or having your period, you should not worry about this.


Subfebrile temperature in a child. What to do?

If a teenager or young child has a subfebrile temperature, first and foremost, make sure that this is not a “temperature tail” (the result of a cold or a viral illness).

Many parents start to panic when their child has a temperature of 37°C, but at the same time they forget that the child has just recently had SARS, flu or tonsillitis.

After ARVI, a child may have subfebrile temperature for 5-14 days. And that would be the norm.



However, if the child has a subfebrile temperature and he cannot explain his condition to you, it is important to contact a competent doctor who will diagnose and determine the exact cause of the temperature increase for further correct treatment.

Normal temperature range for people of different ages

Region

Age 90 120

0-2 years

3-11 years

11-65 years old

Over 65 years old

Axillary 900 03

34. 7°C-37.2°C

35.8°C-36.6°C

35.1°C-36.8°C

35.5°C-36.3°C

90 129

Oral

35.7°C-37.3°C

35.5°C-37.5°C

36.4°C-37.5°C

35.7°C-36.9°C

Rectal

36.6°C-38.0°C 36.6°C-38.0°C

37.0°C-38.1°C

36.1°C-37.3°C

Tympanic 0129

36.1°C-37.7 °С

35.8°С-37.6°С

35.8°С-37.5°С

Internal organs 9000 3

36.3°C- 37.7°C

36.3°C-37.7°C

36.7°C-37.8°C

35.8°C-37.1°C

These temperature ranges can be observed in most people of all ages. Balancing these boundaries remains the norm if the temperature changes under the influence of external factors or characteristics of the organism (this should be clarified with the doctor).

However, if low-grade fever causes discomfort or is accompanied by symptoms of an unknown etiology, your task is to find the cause as soon as possible and begin effective treatment.

The R+Medical Network premium class private clinic in Goloseevsky and Pechersky districts of Kyiv is distinguished by the fact that we provide patients with an integrated approach to both diagnosis and treatment of diseases.

We are not satisfied with a single indicator of tests, we are interested in a detailed analysis of the root cause of subfebrile temperature and its immediate elimination .


And this is achieved by specialists at the highest level, since all doctors of the R + Medical Network clinic are of the highest category, with extensive international work experience and personal values ​​that allow them to always cope with a situation of any complexity.

Therefore, if you feel something is wrong with your health, do not hesitate – seek qualified medical care at a private R+Medical Network clinic. And this is achieved by specialists at the highest level, since all doctors of the R + Medical Network clinic are of the highest category, with extensive international work experience and personal values ​​that allow them to always cope with a situation of any complexity.

In the “one day” mode, you can find all the answers to your questions at an affordable price, without a queue and additional movements.


Make an appointment with a therapist

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Author:

Ganzha Tatyana Valerievna

Therapist, allergist, first category, Experience 15 years

Other blog entries

Subfebrile temperature – why is it dangerous? What to do? Where to go in Kazan? MC Health Formula

36.6 is not a constant body temperature of a healthy person, if you monitor it during the day, then this value will fluctuate slightly. The lowest result, about 36 degrees, will be at the time of morning sleep. If a person is hot after exercise, the temperature may rise slightly

Body temperature is affected by heat, humidity, too warm clothes. In women, there is a slight jump in temperature (by half a degree) on certain days of the menstrual cycle. But it will be a one-time increase. A cause for concern may be an increase in temperature from 37.2 to 37.9 for a period of more than a month – this is subfebrile temperature.

If subfebrile temperature lasts for more than two weeks, and it is accompanied by symptoms such as fatigue, poor sleep, shortness of breath, then the therapist should not be postponed. Often, low-grade fever signals a malfunction in the body when other symptoms have not yet appeared.

Picture taken from stock.adobe.com in the free section stock.adobe.com/en/free


Causes of subfebrile temperature

There are diseases that provoke a slight increase in temperature over a long period.

  • Chronic infectious process (tuberculosis, chronic diseases of the nasopharynx, pancreatitis, cholecystitis, prostatitis, adnexitis, bacterial endocarditis, chlamydia, syphilis, HIV infection).
  • Inflammatory process
  • Oncology
  • Autoimmune diseases (rheumatism, ulcerative colitis, drug allergy, arthritis, postinfarction syndrome)
  • Parasites
  • Pathologies of the endocrine system (thyrotoxicosis, severe menopause)
  • Thermoneurosis (vegetative dysfunction affecting heat transfer)

If the cause of fever is an infection, then it is characterized by:

  • decrease after taking antipyretic;
  • poor tolerance;
  • there are fluctuations throughout the day.

But there are reasons when a healthy person has a subfebrile temperature:

  • overheated
  • under stress
  • when taking certain drugs
  • hereditary factor when a child is born and lives with a fever
  • with activation of the hypothalamus
  • during pregnancy
  • before menses.

Such a temperature is not amenable to the action of antipyretic drugs, is easily tolerated and does not have pronounced daily fluctuations.

Examination will help to find out the cause.

Analyzes and studies at subfebrile temperature.

You should always start with a general practitioner. It is the general practitioner who will refer you for primary tests, and then, after the results obtained, will recommend the appointment of a narrow specialist: an endocrinologist, a cardiologist, a gynecologist, an otolaryngologist, an infectious disease specialist.

Fever for more than two weeks?

Need to submit:

  • General analysis of blood and urine (increased leukocytosis, protein in the urine)
  • Blood for hepatitis B and C, HIV and syphilis
  • Sputum culture for Mycobacterium tuberculosis
  • Urine culture (genital infections) and blood culture (sepsis).

Do:

  • Chest x-ray (tuberculosis, lung abscess)
  • Electrocardiogram (bacterial endocarditis)
  • Pelvic ultrasound (inflammatory diseases)
  • Abdominal ultrasound

If, after the results obtained, the cause is not established, then the patient is sent to take a blood test:

  • for hormones
  • for rheumatoid factor
  • for tumor markers.