ശരീരത്തിന്റെ ഊഷ്മാവ് സാധാരണ നിലയിൽ ഉള്ള ശരീര താപനിലയിൽ36.5–37.5 °C (97.7–99.5 °F)നിന്ന് ഉയർന്നു നിൽക്കുന്ന രോഗലക്ഷണമാണ് പനി. ഇംഗ്ലീഷ്:Fever: ശാസ്ത്രീയമായി Pyrexia (ഗ്രീക്ക്: pyretos / തീ), Febrile response (ലാറ്റിൻ: febris/പനി) എന്നീ പേരുകളിലും അറിയപ്പെടുന്നു. ശരീരോഷ്മാവിന്റെ നിയന്ത്രണ സംവിധാനത്തിലെ ക്രമീകരണത്തിലുണ്ടാകുന്ന വ്യതിയാനമാണിതിനു കാരണം. ഈ ക്രമീകരണ വ്യത്യാസം മാംസപേശികളിൽ മുറുക്കവും അയവും ഉണ്ടാക്കുകയും വിറയൽ അനുഭവപ്പെടുകയും ചെയ്യുന്നു. അതോടൊപ്പം, നെഞ്ചിടിപ്പ് കൂടുക, വിറയ്ക്കുക എന്നീ ലക്ഷണങ്ങളും ഉണ്ടാകാറുണ്ട്. പനി നിയന്ത്രണാതീതമായി കൂടിയാൽ ചുഴലി പോലുള്ള ലക്ഷണങ്ങൾ വരാറുണ്ട്. മലമ്പനി, മഞ്ഞപ്പനി, പക്ഷിപ്പനി, പന്നിപ്പനി തുടങ്ങിയ വിവിധ അസുഖങ്ങൾക്കും ഊഷ്മാവിലെ വ്യത്യാസം എന്ന ഈ ലക്ഷണം ഉണ്ടാവുന്നതുകൊണ്ട് പനി എന്ന പ്രത്യയം ചേർത്ത് അറിയപ്പെടുന്നു.
ഹൈപ്പർതെർമിയ (അമിതതാപം) എന്ന അവസ്ഥയിൽ നിന്നു വ്യത്യസ്തമാണ് പനി. കൂടിയ അളവിലുള്ള താപോത്പാദനം കൊണ്ടോ കുറഞ്ഞ അളവിൽ താപം പുറന്തള്ളുന്നതു കൊണ്ടോ ആണ് ഈ അവസ്ഥ ഉണ്ടാകുന്നത്.

Understanding Fever: Causes, Symptoms, Diagnosis, and Treatment*

Fever is a common physiological response characterized by an elevation in body temperature, often in response to infection, inflammation, or other underlying medical conditions. Fever is typically accompanied by symptoms such as chills, sweating, headache, muscle aches, and fatigue. While fever itself is not usually harmful and serves as a natural defense mechanism against infection, it can sometimes indicate a more serious underlying condition. In this comprehensive guide, we will explore the causes, symptoms, diagnosis, and treatment options for fever.

*Causes of Fever:*

Fever can be caused by various factors, including infections, inflammatory conditions, medications, environmental exposures, and other medical conditions. Common causes of fever include:

1. *Infections:* Fever is often a sign that the body is fighting off an infection caused by bacteria, viruses, fungi, or parasites. Common infectious causes of fever include respiratory infections (e.g., colds, flu), urinary tract infections, gastrointestinal infections, skin infections, and sexually transmitted infections.

2. *Inflammatory Conditions:* Inflammatory conditions such as rheumatoid arthritis, lupus, inflammatory bowel disease, and vasculitis can trigger fever as part of the body's immune response to inflammation. Fever associated with inflammatory conditions is often accompanied by other symptoms such as joint pain, rash, and fatigue.

3. *Medications:* Some medications, particularly certain antibiotics, anticonvulsants, and antipsychotic medications, can cause fever as a side effect. Drug-induced fever typically occurs shortly after starting or increasing the dosage of the medication and resolves once the medication is discontinued.

4. *Heat Exposure:* Prolonged exposure to high environmental temperatures, particularly in hot and humid conditions, can lead to heat-related illnesses such as heat exhaustion and heatstroke, characterized by elevated body temperature, dehydration, and other symptoms.

5. *Autoimmune Disorders:* Autoimmune disorders such as systemic lupus erythematosus (SLE), autoimmune hepatitis, and inflammatory arthritis can cause fever as a result of immune system dysfunction and inflammation affecting multiple organs and tissues.

6. *Cancers:* Certain types of cancer, particularly blood cancers such as leukemia and lymphoma, can cause fever as a result of the body's immune response to cancer cells or as a side effect of cancer treatments such as chemotherapy or radiation therapy.

7. *Other Medical Conditions:* Other medical conditions such as thyroid disorders, blood clots, and inflammatory lung diseases can cause fever as a result of underlying physiological disturbances or immune system dysfunction.

*Symptoms of Fever:*

Fever is characterized by an elevation in body temperature above the normal range, typically defined as a temperature of 100.4°F (38°C) or higher when measured orally. In addition to elevated body temperature, fever may be accompanied by the following symptoms:

1. *Chills:* Many individuals with fever experience chills, which are involuntary muscle contractions and shivering episodes that help raise body temperature to match the set point of the hypothalamus.

2. *Sweating:* As the body temperature rises during fever, the body may respond by sweating in an attempt to dissipate heat and cool down. Sweating may occur during the fever episode or during the recovery phase as the fever resolves.

3. *Headache:* Fever can cause headaches or exacerbate existing headache symptoms, leading to discomfort and pain in the head and temples. Headaches associated with fever are often described as dull, throbbing, or pressure-like in nature.

4. *Muscle Aches:* Fever-related muscle aches, also known as myalgia, are common and may affect various muscle groups throughout the body. Muscle aches may contribute to feelings of fatigue, weakness, and discomfort during fever episodes.

5. *Fatigue:* Fever can cause fatigue, lethargy, and decreased energy levels, leading to feelings of weakness, malaise, and reduced ability to perform daily activities. Fatigue may persist until the fever resolves and energy levels return to normal.

6. *Loss of Appetite:* Many individuals with fever experience a reduced appetite or loss of interest in food, particularly during the acute phase of illness. Loss of appetite may be accompanied by nausea, vomiting, or changes in taste perception.

7. *Dehydration:* Fever-related sweating, increased respiratory rate, and reduced fluid intake can lead to dehydration, characterized by symptoms such as dry mouth, thirst, dark urine, and decreased urine output.

*Diagnosis of Fever:*

Diagnosing fever typically involves a comprehensive evaluation of medical history, symptoms, physical examination, and diagnostic tests. Healthcare providers may use the following approaches to diagnose fever and identify the underlying cause:

1. *Medical History:* Healthcare providers will inquire about symptoms, onset, duration, and severity of fever, as well as any recent exposures, travel history, or underlying medical conditions that may be relevant to the diagnosis.

2. *Physical Examination:* A physical examination may be performed to assess vital signs, including body temperature, heart rate, respiratory rate, and blood pressure. Healthcare providers will also evaluate for signs of infection, inflammation, or other abnormalities that may be contributing to fever.

3. *Laboratory Tests:* Blood tests such as complete blood count (CBC), blood cultures, and inflammatory markers (e.g., C-reactive protein, erythrocyte sedimentation rate) may be performed to assess for signs of infection, inflammation, or other underlying conditions.

4. *Imaging Studies:* Imaging studies such as chest X-ray, computed tomography (CT) scan, or ultrasound may be ordered to evaluate for signs of infection, inflammation, or other structural abnormalities that may be causing fever.

5. *Other Tests:* Additional diagnostic tests such as urine analysis, throat swab culture, stool culture, or serological tests for specific infectious agents may be performed based on clinical suspicion and initial evaluation findings.

*Treatment Options for Fever:*

Treatment for fever aims to reduce body temperature, alleviate symptoms, and address the underlying cause of fever. Treatment strategies may include:

1. *Over-the-Counter Medications:* Over-the-counter medications such as acetaminophen (Tylenol) and nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Advil, Motrin) can help reduce fever and relieve associated symptoms such as headache, muscle aches, and discomfort.

2. *Fluids and Rest:* Drinking plenty of fluids and getting adequate rest are important for supporting the body's immune response, promoting hydration, and facilitating recovery from fever and underlying illness. Consuming clear fluids such as water, electrolyte-rich beverages, broth, and herbal teas can help prevent dehydration and maintain hydration during fever episodes.

3. *Cooling Measures:* Cooling measures such as sponge baths, cool compresses, and lightweight clothing can help lower body temperature and provide relief from fever-related discomfort. Avoiding excessive physical activity and staying in a cool, well-ventilated environment can also help regulate body temperature and promote comfort during fever episodes.

4. *Medications for Underlying Cause:* If fever is caused by an underlying infection or medical condition, healthcare providers may prescribe antibiotics, antiviral medications, or other specific treatments to target the underlying cause and resolve fever.

5. *Monitoring and Follow-Up:* It is important to monitor body temperature, symptoms, and overall health during fever episodes and seek medical attention if fever persists, worsens, or is accompanied by severe symptoms such as difficulty breathing, chest pain, confusion, or seizures