Common Symptoms: Fever, Cough, Fatigue, Pain — What to Do
Some symptoms are so common they start to feel "normal." A fever with no runny nose. A cough that has lasted a month. Fatigue that doesn't go away after sleep. Stomach pain after every meal. Each of these can be harmless — or a signal worth investigating. Let's look at each one separately.
Fever Without Other Symptoms: What It Could Be
Normal body temperature is 97.8–99.0 °F (36.6–37.2 °C). Values up to 99.5 °F (37.5 °C) are considered low-grade; above 100.4 °F (38.0 °C) is a true fever.
If your temperature is 99–99.5 °F for several days with no runny nose, cough, or other obvious symptoms, possible causes include:
- Early viral infection — other symptoms will appear within 1–2 days
- Hidden bacterial infection — urinary tract, dental, or sinus infection
- Autoimmune conditions — rheumatoid arthritis, lupus, Crohn's disease
- Thyroid disorders — hyperthyroidism (overactive thyroid)
- Malignancy — persistent low-grade fever without a cause warrants exclusion
- Physiological variation — in women, temperature rises in the second half of the menstrual cycle
When to see a doctor: fever above 100.4 °F for more than 3 days; low-grade fever lasting more than 2 weeks without an obvious cause; fever accompanied by weight loss, night sweats, or swollen lymph nodes.
Cough Lasting More Than 3 Weeks: When to See a Doctor
An acute cough from a respiratory infection clears up in 1–2 weeks. A cough lasting more than 3 weeks is called subacute; more than 8 weeks is chronic. Chronic cough requires evaluation.
Common causes of a prolonged cough:
- Post-infectious cough — after a respiratory infection, the airway lining takes 3–8 weeks to recover; the cough is dry, nagging, and often worse at night
- Asthma — cough with shortness of breath and wheezing, especially at night and with exercise
- Gastroesophageal reflux (GERD) — stomach acid irritates the throat; cough worsens after meals and when lying down
- Postnasal drip — mucus from the nose drips down the back of the throat, triggering a cough, especially in the morning
- ACE inhibitor medications — a class of blood pressure drugs causes a dry cough in 10–15% of patients
- Chronic bronchitis in smokers — morning cough with mucus production
Red flags — see a doctor immediately: blood in sputum; cough with weight loss; night sweats; shortness of breath at rest; a smoker over 40 whose cough has changed in character.
Persistent Nausea Without Vomiting
Recurring nausea without vomiting is one of the most non-specific symptoms. It can be linked to the stomach, intestines, nervous system, hormones, or psychological state.
Possible causes:
- Gastritis or peptic ulcer — nausea on an empty stomach or after eating, pain in the upper abdomen
- GERD — nausea after meals, heartburn, belching
- Functional dyspepsia — post-meal discomfort without a structural cause
- Pregnancy — nausea in the first trimester, especially in the morning
- Gallbladder disease — nausea after fatty foods
- Medications — antibiotics, NSAIDs (ibuprofen, aspirin), metformin
- Anxiety disorder — nausea as a physical manifestation of anxiety
- Migraine — nausea as an accompanying symptom
When to see a doctor: nausea lasting more than 2 weeks; accompanied by abdominal pain, weight loss, or jaundice; started after beginning a new medication.
Abdominal Pain After Eating
Post-meal pain often points to a specific organ depending on its location and timing.
- Upper-middle pain immediately after eating — gastritis, peptic ulcer, functional dyspepsia
- Right-upper pain 30–60 minutes after a fatty meal — gallbladder (gallstones, biliary dyskinesia)
- Left-upper pain after eating — pancreas (pancreatitis)
- Lower abdominal pain after eating, relieved by a bowel movement — irritable bowel syndrome (IBS)
- Bloating and pain 1–2 hours after dairy products — lactose intolerance
When to seek urgent care: severe sudden pain that doesn't subside; pain with vomiting of bile or blood; pain with high fever; pain radiating to the back or right shoulder.
Night Sweats
Night sweats are episodes of heavy sweating during sleep that soak clothing and bedding. This is different from simply feeling hot — it refers to sweating unrelated to room temperature.
Possible causes:
- Menopause — the most common cause in women aged 45–55, linked to declining estrogen levels
- Infections — tuberculosis, HIV, and bacterial endocarditis classically cause night sweats
- Malignancy — lymphomas, leukemia; sweating is combined with weight loss and swollen lymph nodes
- Thyroid disorders — hyperthyroidism
- Medications — antidepressants, tamoxifen, some antipyretics
- Hypoglycemia — low blood sugar overnight, especially in people with diabetes
- Anxiety disorder
When to see a doctor: night sweats lasting more than 2 weeks; combined with weight loss, swollen lymph nodes, fever, or cough — this combination requires evaluation.
Bitter Taste in the Mouth
A persistent bitter taste is a symptom many people ignore for years. Yet it often points to a specific, treatable problem.
Possible causes:
- GERD and bile reflux — the most common cause. Bile or acid backs up into the esophagus and mouth, especially in the morning and after fatty meals
- Gallbladder disease — biliary dyskinesia, cholecystitis
- Medications — antibiotics, metronidazole, iron supplements cause a metallic or bitter taste
- Dental and gum disease — inflammation produces a bitter taste
- Pregnancy — hormonal changes alter taste perception
- Stress and anxiety — can alter taste sensations
When to see a doctor: bitter taste lasting more than 2 weeks; combined with right-upper abdominal pain, nausea, or yellowing of the skin; appeared after starting a new medication.
If you're unsure what's behind your symptoms, Symptomatica can help you work through them and understand which specialist to see.
Frequently Asked Questions
Is a temperature of 99.1 °F already a sign of illness?
Not necessarily. Body temperature fluctuates throughout the day: lower in the morning, higher in the evening by 0.5–1 °F. After exercise, a large meal, or in hot weather, temperature can briefly rise to 99–99.5 °F. In women, basal temperature rises in the second half of the menstrual cycle. If 99.1 °F persists for several days without an obvious cause, it's worth seeing a doctor.
How long is a post-infection cough considered normal?
A post-infectious cough after a respiratory illness can last up to 8 weeks — that's within normal range. The airway lining recovers slowly, and cough receptors remain hypersensitive. If the cough is dry, gradually improving, and there are no other symptoms, it's reasonable to wait. If the cough worsens, produces mucus, or is accompanied by fever or shortness of breath, see a doctor.
Is morning nausea always a sign of pregnancy?
No. Morning nausea is a classic pregnancy symptom, but it also occurs with gastritis (stomach acid irritates the lining on an empty stomach), GERD, anxiety disorder, hypoglycemia (low blood sugar after overnight fasting), and migraine. If pregnancy is ruled out and morning nausea recurs, it's worth having your stomach evaluated.
Are night sweats always something serious?
No. The most common cause in middle-aged women is menopause. In younger people, anxiety disorder or certain medications are frequent culprits. However, night sweats combined with weight loss, swollen lymph nodes, or prolonged fever are a reason for urgent evaluation.
Bitter taste in the morning — what's the first step?
Start by ruling out simple causes: check whether the bitter taste started after a new medication, and have your teeth and gums examined. If it appears regularly in the morning along with heartburn or belching, GERD or bile reflux is the most likely explanation. See a gastroenterologist.
When is post-meal abdominal pain actually a heart problem?
Upper abdominal pain (epigastric pain) can sometimes be a presentation of a heart attack — especially in older adults and people with diabetes. If post-meal abdominal pain is accompanied by shortness of breath, sweating, pain in the left arm or jaw — this is an emergency. Call emergency services.
Symptomatica is an informational reference service. Not a medical service; does not diagnose or prescribe treatment. For any symptoms, please consult a doctor.