There are many causes of sore throat and fatigue, and many of them are very common. A lot of garden-variety illnesses begin with these two symptoms, but they can also be a signal of more serious illnesses that require medical attention. Viruses and bacterial infections are common causes, and sometimes either intentional or accidental chemical exposure can cause these symptoms as well.
Those who have had a cold or the flu may recall starting out by noticing a sore or scratchy throat and a sense of feeling run down, although this isn’t always the first symptom of the many rhinoviruses or influenza viruses. Sometimes a scratchy throat is so minor it isn’t noticed at first, or it is present without fatigue. Some people feel achy, develop a fever, and get nasal congestion or coughing, too.
A few more serious illnesses can begin with sore throat and fatigue. These two symptoms, which are sometimes accompanied by an aching in the stomach near the spleen, could be a sigh of mononucleosis or chronic fatigue syndrome. The throat is usually extremely sore and not just scratchy or a little uncomfortable with mono. Infections like strep throat are also associated with sore throat and tiredness, and patients with this illness may have other symptoms like fever, swollen glands, rash, and/or stomach ache. Other conditions that may have these two symptoms include mumps, HIV, swine flu, typhoid, meningitis, pertussis (whooping cough), dengue fever, Ebola virus, anthrax, and avian flu, but these are not as common and some are preventable with vaccine.
Certain forms of cancer are also cause tiredness and a sore throat. Lymphoma falls into this group, with the sore throat often caused by swollen lymph nodes. Sometimes, the treatments for cancer result in a depressed immune system, which can leave the patient open to other illnesses. People with cancer should immediately report cold or flu symptoms to a physician.
There are many medications that can cause dry or sore throat and fatigue. Among these are a number of antidepressants, tranquilizers, decongestants, and antihistamines. People who use medication daily may feel fatigued. For example, taking daily pills for allergies may experience low-level tiredness and a scratchy throat.
People can also develop these symptoms if they have significant or low level repeated exposure to certain chemicals. These include some pesticides, and commonly used products like isopropyl alcohol, nail polish remover, window cleaners, pool cleaners, or formaldehyde. Those who seem to have these symptoms chronically and who work around chemicals may want to consult a medical professional about whether chemical exposure could be creating the problem.