Contents
Fever usually occurs at a high temperature, thus the body reacts to infection1. The higher the body temperature, the stronger the manifestations of fever. If the temperature does not decrease for several days, it is urgent to consult a doctor who will find out its causes and prescribe the necessary treatment.
What is a fever
Fever is a non-specific reaction of the body to the effects of pyrogens (biologically active substances that increase body temperature), in which metabolic processes and thermoregulation are disturbed.1. The main symptom of fever is an increase in body temperature.
Depending on the degree of increase in body temperature, fever is:
- subfebrile – 37,2-38 degrees;
- moderate – 38,1-39;
- high – 39,1-40;
- excessive – above 41,12.
Depending on the duration, the following types of fever are distinguished2:
- ephemeral – lasting from several hours to several days;
- acute – up to 15 days;
- subacute – from 16 to 44 days;
- chronic – more than 45 days.
Types of fever
| Constant | Long-term persistent increase in body temperature, its fluctuations do not exceed 1 degree per day | It happens with typhoid and typhus, lobar pneumonia, erysipelas |
| laxative | Pronounced daily fluctuations are 1,5 – 2 degrees. The temperature does not drop to normal | It happens with exudative pleurisy, lung abscess |
| Intermittent | A rapid increase in temperature and an equally rapid decrease to normal numbers or below 36 ° C | Occurs with malaria, pyelonephritis, pleurisy |
| Exhausting | Rapid rise and rapid drop in temperature, fluctuations of 3-4 degrees. Can be repeated several times a day | Characteristic for sepsis, severe forms of tuberculosis |
| Atypical | Temperature fluctuations without a definite pattern | For rheumatism, pneumonia, influenza, dysentery |
| Undulating | A smooth “wave-like” rise in temperature, and then a gradual decrease to normal values. | Accompanies brucellosis, lymphogranulomatosis |
Fever symptoms in adults
Fever is very rarely an independent disease. Often this is one of the symptoms of acute or chronic pathology. It is important to pay attention to specific signs that may indicate a particular disease.3:
- increased body temperature (should take into account the difference between the rectal, mouth and armpit);
- rapid breathing (more than 18 breaths per minute);
- general malaise;
- pain of different localization;
- chills, trembling;
- heat;
- redness of the skin;
- increased sweating;
- frequent urination;
- headache;
- confusion, delirium;
- decreased appetite.
All symptoms do not appear at the same time. Each stage of fever corresponds to certain symptoms.
Causes of fever in adults
The main reason for the increase in body temperature are pyrogens. These are biologically active substances that cause fever and can enter the body from the outside or be formed inside3. Pyrogens change the processes of thermoregulation, which leads to an increase in body temperature and the development of fever.
Pyrogens can be3:
- pathological microorganisms, as well as their toxins and decay products;
- antigens – substances that are considered by the body as foreign;
- any substance that causes inflammation.
There are endogenous (which are formed inside the body) and exogenous (which come from outside), as well as primary and secondary pyrogens. Primary pyrogens are various infectious pathogens, poisons and toxins, as well as substances that are formed in the body as a result of injury, necrosis or aseptic inflammation. They provoke the appearance of secondary pyrogens, which affect the thermoregulatory center and cause fever.
Fever at a temperature in an adult
Fever accompanied by temperature can be caused by various causes – both infectious and non-infectious.4.
In the first case, fever develops in response to the penetration of an infectious agent into the body, as well as to the toxins and waste products produced by it. Fever is usually caused by:
- viral infections;
- bacterial infections;
- parasitic infections.
Non-infectious factors include4:
- massive hemorrhages;
- poisoning with poisons of plant, animal and industrial origin;
- malignant neoplasms;
- mechanical damage (trauma);
- condition after a burn;
- diseases of the endocrine glands (hyperthyroidism, pheochromocytoma);
- psychogenic states (neurosis, emotional overstrain, diseases of the central nervous system);
- allergic reaction;
- autoimmune diseases;
- taking certain medications.
Fever without fever in an adult
Fever without an increase in temperature is impossible, as it affects the processes of thermoregulation. But chills without fever occur, as it is not always a symptom of fever.
Consider the most common causes of chills without fever5:
- hormonal changes in the body (pregnancy, menopause);
- neuropsychic overstrain;
- sharp changes in blood pressure;
- diseases of the endocrine system (a feeling of chills may appear in the evening);
- hypothermia;
- bleeding;
- metabolic disease.
Treatment of fever in adults
Since fever is a non-specific reaction of the body, there is no specific treatment for it. It is only possible to alleviate the condition before the doctor arrives and finds out the cause of the disease.
Drinking plenty of fluids
A sufficient amount of fluid in the body allows you to quickly remove the products of intoxication and significantly alleviate the condition.6. According to clinical recommendations, the required volume of liquid is 20-40 ml per 1 kg of human weight. It can be non-carbonated water, juices, fruit drinks, tea. Drinks should not be overly sweet, and tea should not be strong.
Antipyretics
Paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs), such as Ibuprofen, Diclofenac, Ketoprofen, will help relieve fever. They suppress the inflammatory process and lower the temperature.6. Paracetamol is an analgesic with antipyretic and analgesic effects.
Paracetamol and NSAIDs should be taken only when the body temperature rises above 38 degrees and if you feel unwell. If the high temperature is tolerated satisfactorily, then it is better not to take antipyretics.6.
As for other medicines or traditional medicine, you can resort to them only after consulting a doctor.
Prevention of fever in adults at home
There is no specific prevention of fever. It is important to follow the rules of a healthy lifestyle and take care of your health.
There are 3 types of prevention:
- Primary – compliance with the rules of a healthy lifestyle, elimination of the causes and predisposing factors for the development of diseases.
- Secondary – involves the active detection of diseases (especially those that are asymptomatic).
- Tertiary – actively monitoring the development of fever, preventing complications and worsening of the condition.
Popular questions and answers
We discussed important issues related to fever with therapist Tatyana Pomerantseva.
How is fever different from chills?
Chills are the first stage of fever in infectious diseases, injuries, and some pathological processes. Chills also occur with hypothermia.
Thus, chills are simply a sensation that may not only occur with fever. An increase in body temperature during chills is also not mandatory.
What are the main stages of a fever?
• Rise in temperature. The process of thermoregulation changes: heat production prevails over heat transfer. Vasoconstriction occurs, so much less warm blood enters the tissues. Against this background, there are such phenomena as “goosebumps”, chills, muscle tremors.
• Temperature retention. The processes of heat production and heat transfer become equivalent, the vessels expand, and warm blood enters the tissues again. There is a feeling of heat, redness of the skin. Keeping the temperature can be for several hours or days.
• Decrease in temperature (may be gradual or abrupt). The decrease in temperature occurs only after the formation of pyrogens (substances that increase body temperature). When the temperature drops, the blood vessels dilate, the body tries to get rid of excess fluid in the body. This is manifested by profuse sweating, an increase in the amount of urine excreted.
When should you call a doctor if you have a fever?
• the appearance of convulsions;
• loss of consciousness or confusion;
• severe headache, which is accompanied by impaired vision, movement, speech;
• loss of sensitivity;
• incessant vomiting;
• blood in vomit or feces;
• lack of urination for more than 12 hours;
• sharp pain in the abdomen;
• pronounced edema;
• pain in the region of the heart radiating to the arm, neck, shoulder;
• shortness of breath, inability to inhale or exhale.
Sources of:
- F.I. Wismont. Selected lectures on pathophysiology. Minsk, 1997. https://e-catalog.nlb.by/Record/BY-NLB-br95657
- Fever pathogenesis, mechanism of action of antipyretics. Rational use of antipyretics in children. A guide for doctors. Ministry of Health of the Russian Federation, Russian Association of Pediatric Research Centers, Moscow Research Institute of Pediatrics and Pediatric Surgery. M., 2003. https://komarovskiy.net/lib/racionalnoe-primenenie-zharoponizhayushhix-sredstv-u-detej.html
- ON THE. Korovina, I.N. Zakharova, E.M. Ovsyannikov. Fever. The variety of reasons and the complexity of the solution. Journal “Medical Council”, M., 2013. https://cyberleninka.ru/article/n/lihoradka-mnogoobrazie-prichin-i-slozhnost-resheniya
- Pilshchikova V.V., Bondina V.M., Gubareva D.A., Puzanova E.A. Prevention of diseases: a textbook for students of medical and pediatric faculties. – Krasnodar, KubGMU of the Ministry of Health of Russia, 2016 -224 p. https://www.ksma.ru/cms/files/princeca.pdf
- Клинические рекомендации «Грипп и ОРВИ» 2019 год. https://www.rnmot.ru/public/uploads/RNMOT/clinical/2021/%D0%9A%D0%A0%20%D0%9E%D0%A0%D0%92%D0%98.pdf