Why Do I Always Feel Tired and Weak?

Occasional tiredness is normal, but if you are frequently or constantly tired, you are likely suffering from fatigue. It may be brought on by a minor condition or it may signal a life-threatening illness. Weakness is uncommon in young, healthy adults and therefore warrants an evaluation. Frequent weakness should be cause for concern at any age. Chronic fatigue syndrome -- a disorder that causes extreme fatigue -- affects more than one million people in the United States. Schedule a physical examination if you always feel tired or weak -- this could be a sign of a serious medical condition.

Mental Conditions

Fatigue is one of the classic symptoms of depression, often causing sufferers to spend many waking hours in bed. Conditions such as generalized anxiety disorder, panic disorder and the depressed phase of bipolar disorder can also cause people to feel extraordinarily tired. Treatment typically involves psychotherapy or medication for the underlying psychiatric condition.

Physical Conditions

Causes of Fatigue and Low Fever

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An infection can cause excessive tiredness and, when severe, a feeling of weakness. This occurs from the body's attempt to fight off the infection and the effects of chemicals the body produces in response to the infection. Treatment of the chronic infection with antibiotics, antiviral medications or other medicines usually brings relief of fatigue within days or relief of weakness within a couple of weeks.

Cancer, heart disease, heart failure, diabetes and a host of other chronic conditions can lead to feelings of excessive tiredness and weakness. The American Heart Association explains that heart failure causes tiredness, because the weakened heart cannot pump blood forcefully enough to meet the body's needs. Similarly, other chronic conditions may leave the sufferer sidelined much of the time. Treatment typically consists of medication, lifestyle changes, dietary modifications and, occasionally, surgery.

Lifestyle Factors

Most Americans fail to get the seven to eight hours of sleep needed each night for optimum health. This can lead to chronic fatigue and feelings of weakness. Sleep apnea, a condition in which the individual stops breathing repeatedly during sleep, is a serious sleep disorder that leads to daytime fatigue. Sleep problems are corrected by improved sleep hygiene, going to bed earlier, keeping distractions out of the bedroom, improved sleep management and maintenance of a proper weight. Occasionally, pharmacological, surgical or device intervention is needed.

A nutritional deficiency may be to blame for fatigue in an otherwise healthy individual. Rarely, such a deficiency may lead to weakness. Common culprits include iron deficiency and vitamin B deficiencies. Generalized malnutrition due to poor diet, starvation, eating disorders, intestinal worms, alcoholism or digestive disorders may also be responsible. Treatment involves correction of the underlying deficiency and maintenance of a nutritious diet rich in vitamins, minerals, protein, complex carbohydrates and healthy fats.


Exercise & Starvation

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Many medications cause fatigue as an adverse effect, and some may also cause weakness. Chemotherapy drugs, anti-anxiety drugs, blood pressure medications and medicines for sleep are notorious culprits. Occasionally, the medication can be discontinued or changed, but often the tiredness and weakness must be dealt with by limiting activities and accommodating frequent rest periods.