Vague symptoms often make it tough to know what’s behind them and whether it’s time to see a physician, such as when a cough lingers for weeks or achy joints become swollen and inflamed.

Here’s how to tell the difference between a passing symptom and one that calls for a medical evaluation.

Headache

Headaches often bring patients to a neurologist’s office, says neurologist Ravinder Singh, MD, of Premier Neurology Medical Group.

“Tension-type headaches are the most common and affect nearly 40% of the population,” he notes. “Most headaches do not have an underlying cause and are labeled primary headaches."

Among symptoms that imply an underlying, secondary cause such as a tumor, infection or bleeding is a headache that reaches peak intensity within seconds or minutes, or feels like the “worst headache” of your life.

Likewise, there could be an underlying cause if you have a headache triggered by:

• Coughing
• Bending over
• Sexual activity
• Other physical exertion
• A headache that starts or increases after trauma to the head or neck

Another possible cause for concern are headaches with neurological symptoms, such as:

• Speech difficulties
• Balance problems
• Visual changes
• Numbness or weakness, especially on one side of the body.

A headache accompanied by memory loss or confusion, as well as that associated with fever or neck stiffness, should be checked out.

The onset of headaches after age 40 or for the first time in any patient, Singh says, also may indicate some root problem.

Cough

As with headaches, a cough can crop up on its own or be among a group of other symptoms.

Coughing may be due to:

• A cold or the flu
• COVID-19
• Allergies
• Asthma
• Smoking
• GERD (gastro-esophageal reflux disease)
• Bronchitis
• Pneumonia

You want to consider several factors when looking for reasons behind a cough, according to Mary Beth Miller, MD, an internist specializing in family medicine.

“I look at the season, since a lot of different things are out there at different times of the year such as allergies or cold and flu,” Miller says.

The person “may be immune-compromised, such as in cases of chemotherapy treatments,” Miller adds. “But usually a cough is due to a virus or possibly allergies.” A virus will run its course in 7 to 10 days, while a cough due to allergies can vary in length.

Acute coughs typically begin suddenly and accompany a cold, flu or acute bronchitis, and last between two to three weeks.

Chronic coughs lasting longer than this time may be due to allergies, asthma, chronic obstructive pulmonary disease (COPD), GERD or as a side effect of some medicines.

“A cough that does not go away within 10 days should be checked,” says Miller. A secondary bacterial infection may be at work, or the person may have underlying asthma and not know it.

A cough accompanied by other symptoms of COVID-19—such as fever, shortness of breath or difficulty breathing, muscle aches or headaches, sore throat, a congested or runny nose, nausea or diarrhea and a sudden loss of taste and smell—should result in prompt testing.

Sore Throat

Sore throat symptoms vary depending on the cause and may include:

• Pain or a scratchy sensation in the throat
• Difficulty swallowing; dry throat
• Sore swollen glands (lymph nodes) in the neck or jaw
• Swollen, red tonsils
• White patches on the tonsils
• Sore throat accompanied by a hoarse voice

A viral infection causes the majority of sore throats, such as those caused by a cold or flu. Streph throat, a bacterial infection, requires treatment with antibiotics.

“In the same way coughs usually run their course, a sore throat typically clears up within three to five days,” says Miller.

The age of the person may provide signs as to the cause of the symptoms, says Miller, noting that a sore throat in a teen may be a sign of mononucleosis, a viral infection, but be due to something else in an older adult.

Signs you should seek immediate care for a child with a sore throat include difficulty breathing or swallowing and unusual drooling, which may indicate an inability to swallow.

Adults with sore throats lasting longer than a week should also seek medical attention, especially if the sore throat is accompanied by a fever, upset stomach and/or swollen glands.

Other signs of a possible more serious underlying cause in adults include:

• Difficulty swallowing or breathing
• Inability to open your mouth
• Joint pain
• Earache
• Rash
• Fever higher than 101°F
• Blood in the saliva
• Frequently occurring sore throats
• A lump in your neck
• Hoarseness lasting more than two weeks

“Left untreated the body’s immune system will almost always take care of itself,” says Miller. “But when you don’t take care of the infection you could risk damaging your heart valves or kidneys, although the likelihood is rare.”

Dizziness

For symptoms of dizziness, you want to distinguish between light-headedness or feeling faint versus vertigo, says neurologist Allen Towfigh, MD.

“The latter refers to the sensation that one’s surroundings are moving when they are, in fact, standing still,” Towfigh says.

Vertigo may be caused by crystals inside the ear dislodging and sending the brain mixed signals. Known as benign paroxysmal positional vertigo (BPPV), this can trigger significant nausea and vomiting, says Towfigh.

On the other hand, vertigo associated with Meniere’s disease is due to an inner ear dysfunction and typically links with tinnitus (ringing in the ears) and hearing loss. Double vision, muscle weakness and trouble speaking along with vertigo may indicate a stroke.

In contrast, light-headedness or feeling faint is a less descriptive term with a longer list of potential causes such as dehydration, according to Towfigh. “Medications can also commonly cause light-headedness and feeling faint,” he adds.

Other possible causes include a drop in blood pressure due to an abnormal heart rhythm (arrhythmia) or a change in body position, such as when standing from a seated position.

“It is important to investigate vertigo and light-headedness to determine whether changes need to be made to medications or dosing and to ensure there is no cardiac abnormality,” Towfigh says.

Back Pain

From a constant, dull ache to a sudden pain, 8 out of 10 people can expect to experience back discomfort at some point in their lives.

“Age, arthritis and disc degeneration often play a role in back pain,” says Towfigh.

Scoliosis, an improper or exaggerated curve of the spine, or narrowing of the spinal canal or of the spaces where the nerves exit (spinal stenosis and foraminal stenosis, respectively), may also contribute to discomfort, he notes.

Most back pain goes away on its own over time. Severe pain lasting longer than three days or back pain following an injury—such as from falling from a height or from a hard, ground-level fall—should be checked by your healthcare provider.

In addition, seek medical attention if you experience a sudden onset or dramatic increase in the level of pain.

“This can be a sign of a disc rupture or herniated disc, or a compression fracture in older adults or those suffering from weakened bones,” says Towfigh.

Pain traveling down one or both legs, a possible sign of nerve compression (sciatica), is another reason to seek medical attention. Weakness or difficulty walking or going up and down stairs may also indicate nerve compression.

Finally, see your healthcare provider if pain worsens at night or while lying flat.

Pain felt when lying down, especially when the pain starts when lying down, may indicate disc degeneration, a sprain or fracture, kidney stones or various forms of arthritis, and should always be evaluated by a medical professional.

Joint Pain

A common complaint (especially with advancing age), joint pain often is the result of simple wear and tear. It can mostly be treated with ice and rest.

Limping, difficulty getting around, and being disabled by joint pain may indicate that it’s time to visit your health care professional for a medical evaluation. Acute pain may indicate joint infection.

Fatigue

Feeling tired and fatigued is not only a very common symptom but also one of the hardest to figure out, says Miller.

“Fatigue could indicate anything from cancer to heart disease but is most often simply sleep deprivation,” she says.

Lifestyle habits, psychological conditions and certain health issues can all result in fatigue. For example:

• Alcohol use or abuse
• Excessive physical activity or lack of activity
• Not enough sleep
• Unhealthy eating habits
• Medications such as cold and cough medicines or antihistamines
• Grief
• Sadness
• Anxiety
• Depression
• Stress

Screening for the cause of fatigue starts with looking at the most common physical concerns that may be causing it, says Miller. “We screen for issues that are easy to determine, such as sleep apnea and depression; then we move to the lab."

“Medicine is not black and white,” Miller adds. “It often takes a lot of time to figure out what’s causing the symptoms.”