Fever in Adults: When to See a Doctor (and When to Go to Hospital)

Status: Pending Qualified Medical Review. This article has not yet been reviewed by a qualified medical professional.

Fever is one of the most common reasons people in Bangladesh look for a doctor. Most fevers are caused by viral infections and get better on their own within a few days. But in a country where dengue, typhoid and other infections are common, it is not always wise to "just wait and see".

This guide explains when to see a doctor for fever and helps you decide what to do: care for yourself at home, speak to a doctor soon, or go to hospital now.

What Counts as a Fever?

Normal body temperature is around 37°C (98.6°F), though it varies a little between people and through the day. The NHS defines a high temperature (fever) in adults as 38°C (100.4°F) or above.

How to measure it correctly

• Use a digital thermometer — they are cheap and widely available in pharmacies
• Measure under the tongue or in the armpit, following the instructions
• Wait 15–20 minutes after eating, drinking or bathing
• Write down each reading with the time. This record is very useful for your doctor

Feeling hot to touch is not reliable. A number is far more helpful.

Why Do We Get Fever?

Fever is the body's natural response to infection. It helps the immune system fight germs. Common causes in Bangladesh include:

• Viral infections: common cold, flu, COVID-19
• Dengue and chikungunya, especially in and after the monsoon
• Typhoid (enteric fever) from contaminated food or water
• Urinary tract infections (UTI)
• Chest infections such as pneumonia
• Skin infections or infected wounds
• Malaria, mainly in certain hill and border districts
• Less often: tuberculosis, inflammatory diseases, or reactions to medicines

The cause matters more than the number on the thermometer.

Caring for a Mild Fever at Home

If you feel unwell but can eat, drink and move around, and you have no red-flag signs (listed below), these steps usually help:

1. Rest. Take a break from work or study.
2. Drink plenty of fluids. Water, ORS, soup, dab (green coconut) water. Aim for pale yellow urine.
3. Dress lightly and keep the room ventilated. Do not wrap yourself in heavy blankets.
4. Paracetamol can reduce fever and aches. Follow the dose on the label or as your doctor advises. Do not exceed the maximum daily dose, and avoid taking several products that all contain paracetamol.
5. Sponging with lukewarm water can make you feel more comfortable. Avoid ice-cold water.
6. Eat light, simple food like rice, khichuri, soup or fruit.

A note on painkillers in dengue season

If dengue is possible, avoid ibuprofen, aspirin and diclofenac unless a doctor has ruled dengue out. The WHO advises against these medicines in dengue because they can raise bleeding risk.

Do not start antibiotics on your own

Many fevers are viral, and antibiotics do nothing for viruses. Taking leftover or pharmacy-bought antibiotics can hide the real cause, cause side effects, and add to antibiotic resistance — a serious problem in Bangladesh.

When to See a Doctor Soon

Consult a doctor (online or in person) within a day if:

• Fever lasts more than 3 days, or keeps coming back
• Fever is 103°F (39.4°C) or higher repeatedly
• It is dengue season and you have fever with body ache, eye pain or rash
• You have burning urine, back or side pain
• You have a cough with yellow/green phlegm or chest discomfort
• You have diarrhoea or vomiting with fever
• You have a long-term condition: diabetes, kidney disease, heart disease, HIV, cancer, or you take steroids or other medicines that weaken immunity
• You are pregnant
• You are over 65
• You recently travelled to an area with malaria
• You have unexplained weight loss or night sweats with fever for weeks

Example

Shafiq, 45, has diabetes. He has had a fever of 101°F for two days with burning urine. Because of his diabetes and urinary symptoms, he should speak to a doctor promptly rather than waiting. A doctor may advise a urine test and decide on treatment.

Red Flags: Go to Hospital Immediately

Go to the nearest emergency department or call 999 if fever comes with any of the following:

• Stiff neck, severe headache, or dislike of bright light
• Confusion, extreme drowsiness, or a fit (seizure)
• Difficulty breathing or chest pain
• A rash that does not fade when you press a glass against it
• Bleeding from gums or nose, vomiting blood, or black stools
• Severe belly pain or repeated vomiting (3+ times in 24 hours)
• Very little or no urine, cold and clammy hands and feet
• Fainting or feeling very weak and unable to stand

In dengue, warning signs often appear after the fever settles, so keep watching for 48 hours after the temperature drops.

Tests a Doctor May Suggest

Your doctor will choose tests based on your symptoms and how many days you have been sick. Common ones include:

• CBC (complete blood count) — infection clues, platelets (see dengue platelet count explained)
• Dengue NS1 antigen — early in fever
• Urine routine examination — for UTI
• Blood culture or other tests — if typhoid is suspected
• Chest X-ray — if a chest infection is likely
• Malaria test — if you live in or visited a malaria-risk area

Tests done too early or too late can be misleading, so it helps to ask a doctor before going to a lab.

How to Prepare for a Fever Consultation

Have this ready before talking to the doctor:

• Fever chart: date, time and reading
• Day the fever started
• Other symptoms: cough, urine changes, rash, diarrhoea, pain
• Medicines taken so far, including doses and times
• Existing conditions and allergies
• Photos of any test reports
• Whether anyone else at home or work is sick

Frequently Asked Questions

Is 99°F a fever?

Generally no. 99°F is within or close to normal. The NHS considers 38°C (100.4°F) or above a high temperature in adults.

How many days of fever is too long?

If fever lasts more than 3 days, or you have red-flag signs at any time, see a doctor.

Should I take a bath during fever?

A lukewarm bath or sponging is fine and may make you feel better. Avoid very cold water.

Can I take paracetamol and ibuprofen together?

Do not use ibuprofen if dengue is possible. Otherwise, ask a doctor or pharmacist before combining medicines.

Why does my fever come back after paracetamol?

Paracetamol lowers temperature for a few hours but does not treat the cause. Fever returning is common in infections. If it continues beyond 3 days, consult a doctor.

Can an online doctor help with fever?

Yes, for fevers without red flags (read our guide to consulting a doctor online in Bangladesh). A doctor can review your symptoms and reports, suggest tests, and tell you if you need in-person care.

Speak to a Doctor About Your Fever on ShifaMate

If you have a fever without danger signs and want advice on tests or home care, you can consult a verified MBBS doctor through ShifaMate. Send your temperature record, symptoms and reports in the app. You can also browse ShifaMate doctors.

For any red-flag symptom, go to hospital immediately or call 999.

References

• NHS. Fever in adults
• NHS. High temperature (fever) in adults — when to get help
• World Health Organization. Dengue and severe dengue
• World Health Organization. Typhoid
• World Health Organization. Antimicrobial resistance
• DGHS Bangladesh

This article is for general information and does not replace advice from a qualified doctor.