Persistent low grade fever: Causes and treatments

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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.

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March 18, 2021 | Blog

Feeling tired, unwell, and have warm skin? You may have a low-grade fever. This is a very common symptom of various minor diseases. But sometimes, you can also have a persistent low-grade fever. Here’s what you need to know about this type of fever and how you can treat it.

What Is a Low-Grade Fever?

There are three different levels of fevers: low-grade fever, regular fever, and high-grade fever. A low-grade fever is a slight elevation of the normal body temperature. It’s a minor fever that causes a lower temperature than a regular fever.

Officially, there’s no standard temperature for a low-grade fever. But, these three numbers can help you understand where a low-grade fever stands compared to other types of body heat elevation.

The normal average body temperature is 97°F to 99°F (36.1°C to 37.2°C). The CDC categorizes body temperature as a fever above 100.4°F (38°C). And anything above 103°F (39.4°C) would count as a high-grade fever. 

Based on this, it’s fair to assume that a low-grade fever is anything between 99°F (37.2°C) and 100.4°F (38°C).

Low-Grade Fever Signs and Symptoms

The best way to check if you have a low-grade fever is to check your temperature. You can do this with a thermometer. But, there are other signs and symptoms that appear when you have elevated body temperature. These include:

• Warm skin
• Flushed cheeks
• Sweating
• Chills and shivering
• Glassy eyes
• Muscle aches
• Headache 

You may also experience other symptoms related to the cause of your fever. For example, a cough, runny nose, or sore throat are indicators of the common cold or flu. These additional symptoms can reveal why you have a low-grade fever.

Causes of Low-Grade Fever

Your body constantly works to maintain your optimal internal temperature. This varies based on your hormones, physical activity, and even nutrition. It also adapts to the temperatures of your environment.

However, sometimes your body needs to elevate your temperature above this ideal level. It usually happens to fight off bacteria or viruses. That’s why a low-grade fever is a common symptom of a number of mild diseases.

The common cold and the flu are the two most common causes of a low-grade fever. But viral pneumonia and bronchitis can also cause it (along with a persistent cough). 

Children can experience a low-grade fever from a number of childhood illnesses. These can range from chickenpox to measles. Often, children have back-to-back viral infections. This makes it seem like the low-grade fever is longer than usual.

Other Diseases That Cause a Low-Grade Fever

Viral respiratory infections are the most common cause of low-grade fevers. But, there are other illnesses and circumstances that can also ignite it.

• Urinary tract infection: A persistent fever can be a sign of a UTI for both adults and children. If you feel pain or burning while peeing, and you have blood in your urine, it’s worth seeing a doctor about it.
• Medications: Starting a new medication can cause a “drug fever”. For the first week and a half, your elevated body temperature may be a normal sign. 
• Stress: Even stress can cause a low-grade fever. This is called a psychogenic fever. Fever-reducing medication won’t help with this type of elevated body temperature.
• Tuberculosis: Tuberculosis (TB) is an extremely contagious bacterial disease. Painful, bloody coughing, and night sweats are other common symptoms. 
• Autoimmune diseases: A number of autoimmune diseases cause a persistent low-grade fever. Multiple sclerosis and rheumatoid arthritis are two common ones.
• Thyroid issues: Thyroiditis can cause a low-grade fever, thyroid inflammation, fatigue, and muscle pain. 
• Cancer: Certain cancers can cause unexplained persistent elevated temperature.  Lymphomas and leukemias in particular. Seek out a doctor immediately if you’re worried about your symptoms.

Low-Grade Fever Treatments and Remedies

Usually, low-grade fevers disappear quickly. However, if you’re feeling unwell or your symptoms develop, you can treat a fever at home with natural remedies.

When you have a fever, it’s important to get plenty of rest. Drinking fluids can also help get you feeling better. 

You can also take over-the-counter medicines to lower your fever and ease your symptoms. Acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, aspirin, and naproxen are good for fever relief.

Talk to a doctor before giving infants under 3 months of age medication. Generally, it’s safe for children under 12 to take acetaminophen and ibuprofen to relieve fever symptoms. However, don’t give children under 12 years old aspirin. This can cause a serious disorder called Reye’s syndrome.

When to See a Doctor?

For adults, a low-grade fever is usually nothing to worry about. But, it’s worth monitoring your body temperature to see if it rises. If you develop a fever of 100. 4°F – 103°F (38°C – 39.4°C), and it doesn’t get better after three days, you should contact a doctor. And if your fever goes above 103°F (39.4°C) at any time, you should seek out medical attention immediately.

For infants younger than 3 months, any elevation to their normal temperature is a sign of infection. Call a pediatrician if your baby has a consistent low-grade fever. Irritability, lethargy, diarrhea, and a cough are common accompanying symptoms to monitor.

If your child has a low-grade fever but they’re playing, eating, and drinking normally, it’s not cause for concern. Still, if their low-grade fever lasts more than three days, you should contact a doctor about it. 

In certain cases, it’s best to take your child to the doctor. If they’re irritable, vomiting, have diarrhea, or a fever after being in a hot car, their low-grade fever could be another symptom of illness.

Talk to a Doctor About Your Low-Grade Fever

While a low-grade fever by itself isn’t a cause for concern, it can be a sign of a serious underlying illness. If you have a persistent low-grade fever, or you’re worried about other symptoms, it’s best to see a doctor about it.

Luckily, you don’t even need to leave the comfort of your home to speak to a professional. You can book an online consultation appointment with Carefree MD.

Our board-certified doctors offer quality medical care with the technology of telemedicine. To talk to a physician without leaving your home, all you need is a Carefree MD Card.

Worried about your low-grade fever? Sign up for Carefree MD to discuss your symptoms, get treatment, and find relief with telemedicine today!

The Carefree MD blog is not meant to be a substitute for professional medical advice, diagnosis, or treatment. The text and pictures within the content are intended for information purposes only. Readers should consult with a licensed doctor or healthcare professional before seeking treatment.

The Carefree MD Card is not insurance and Carefree MD is not an insurance provider.

What to do at a temperature without symptoms of the disease > Rubric in Samara

The temperature, which is not much different from the norm, but is already a sign of ill health, is usually called low-grade in medicine.

In this situation, the thermometer may show 37.0 – 37.5°C for a long time. Sometimes the indicators can reach 37.9 ° C. If no other symptoms bother a person, doctors will have to conduct a series of additional tests to understand the cause. Prolonged subfebrile temperature is a special subject of study in therapeutic practice. Patients with such complaints come to the appointment quite often. According to statistics, in 70 – 80% of cases, protracted subfebrile condition occurs in young women with signs of asthenia, in those who suffer from increased fatigue, weakness, irritability, nervousness, have sleep disturbances and other psychopathological disorders. If the fever persists for more than a month or two, then a comprehensive examination is necessary.

Causes

Increased body temperature is caused by certain proteins – pyrogens. They can enter the body from the external environment or be produced spontaneously inside it. These proteins have a connection with the hypothalamus, activate the immune system and affect the general well-being of a person.

In some cases, subfebrile temperature may indicate that a disease has been infected. In others – about a malfunction in the body. Also, sometimes there are congenital pathologies that cause an increase in temperature.

Disorder of thermoregulation can serve as one of the signs of vegetovascular dystonia. With such a disease, a temperature often appears without symptoms of a cold. A person complains of heaviness in the head, weakness, pain. The heat in the body is abruptly replaced by chills. Cold palms and feet may indicate the local nature of thermoregulation failures. In most patients with dystonia, fever can persist for up to several months.

There are cases when low-grade fever causes an increase in the number of simple microbes, which in normal times are not dangerous. This is due to a weakened immune system. The reason for the increase in temperature can also be autoimmune processes, when the body’s defenses mistakenly begin to attack healthy tissue.

— In case of any increase in temperature, you should contact your local doctor. The specialist will first prescribe a general blood and urine test. Based on their results, he will decide on further examination and treatment. In general, absolutely any stress, including emotional stress, can affect the increase in body temperature. Oleg Fatenkov, chief therapist of the Samara region

In addition, doctors say that often a temperature of 37.0 – 37.5 ° C is a sign of an allergy of a latent or overt course. If the indicator reaches 38 ° C and lasts for a long time, then this can be a sign of serious diseases: bronchitis, sinusitis, tuberculosis, latent infections, tumor processes.

Subfebrile condition can also be caused by changes in temperature, stress, hormonal imbalance, and taking certain medications.

What to do?

In any case, a visit to a specialist is necessary. Do not try to bring down the temperature at home with drugs without the advice of a doctor.

Usually low-grade fever does not require taking antipyretics. However, there are exceptions. For example, it is necessary for pregnant women, people with diseases of the nervous system, and patients who are prone to convulsions to bring down a temperature that exceeds 37.50 C.

Instead of medicines, you can try to stabilize the emotional state and relieve tension, do aromatherapy, put a cloth soaked in water on the forehead and temples, drink fortified tea. But if this does not help, it is necessary to undergo an examination, since serious problems can be behind a minor failure. Most often, doctors prescribe a general and biochemical blood test, a general urinalysis, an ultrasound examination of internal organs, a study for genital infections, and recommend that you undergo an examination with a dentist.

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What to do at a temperature without symptoms of the disease > Rubric in Samara

The temperature, which is not much different from the norm, but is already a sign of ill health, is usually called low-grade in medicine.

In this situation, the thermometer may show 37.0 – 37.5°C for a long time. Sometimes the indicators can reach 37.9 ° C. If no other symptoms bother a person, doctors will have to conduct a series of additional tests to understand the cause. Prolonged subfebrile temperature is a special subject of study in therapeutic practice. Patients with such complaints come to the appointment quite often. According to statistics, in 70 – 80% of cases, protracted subfebrile condition occurs in young women with signs of asthenia, in those who suffer from increased fatigue, weakness, irritability, nervousness, have sleep disturbances and other psychopathological disorders. If the fever persists for more than a month or two, then a comprehensive examination is necessary.

Causes

Increased body temperature is caused by certain proteins – pyrogens. They can enter the body from the external environment or be produced spontaneously inside it. These proteins have a connection with the hypothalamus, activate the immune system and affect the general well-being of a person.

In some cases, subfebrile temperature may indicate that a disease has been infected. In others – about a malfunction in the body. Also, sometimes there are congenital pathologies that cause an increase in temperature.

Disorder of thermoregulation can serve as one of the signs of vegetovascular dystonia. With such a disease, a temperature often appears without symptoms of a cold. A person complains of heaviness in the head, weakness, pain. The heat in the body is abruptly replaced by chills. Cold palms and feet may indicate the local nature of thermoregulation failures. In most patients with dystonia, fever can persist for up to several months.

There are cases when low-grade fever causes an increase in the number of simple microbes, which in normal times are not dangerous. This is due to a weakened immune system. The reason for the increase in temperature can also be autoimmune processes, when the body’s defenses mistakenly begin to attack healthy tissue.

— In case of any increase in temperature, you should contact your local doctor. The specialist will first prescribe a general blood and urine test. Based on their results, he will decide on further examination and treatment. In general, absolutely any stress, including emotional stress, can affect the increase in body temperature. Oleg Fatenkov, chief therapist of the Samara region

In addition, doctors say that often a temperature of 37.0 – 37.5 ° C is a sign of an allergy of a latent or overt course. If the indicator reaches 38 ° C and lasts for a long time, then this can be a sign of serious diseases: bronchitis, sinusitis, tuberculosis, latent infections, tumor processes.

Subfebrile condition can also be caused by changes in temperature, stress, hormonal imbalance, and taking certain medications.

What to do?

In any case, a visit to a specialist is necessary. Do not try to bring down the temperature at home with drugs without the advice of a doctor.

Usually low-grade fever does not require taking antipyretics. However, there are exceptions. For example, it is necessary for pregnant women, people with diseases of the nervous system, and patients who are prone to convulsions to bring down a temperature that exceeds 37.50 C.

Instead of medicines, you can try to stabilize the emotional state and relieve tension, do aromatherapy, put a cloth soaked in water on the forehead and temples, drink fortified tea. But if this does not help, it is necessary to undergo an examination, since serious problems can be behind a minor failure. Most often, doctors prescribe a general and biochemical blood test, a general urinalysis, an ultrasound examination of internal organs, a study for genital infections, and recommend that you undergo an examination with a dentist.