Chronic fatigue, tiredness or low energy can negatively affect performance.

Tiredness and fatigue are associated with a variety of health condition including anemia, depression, fibromyalgia, insomnia, allergic rhinitis and psychiatric disorders.

Tiredness is also a common side effect of medications. Some of the common drugs that can make you tired are;




Antidepressants are commonly prescribed medications, especially for women (Women are twice as likely as men to take antidepressants, according to the National Center for Health Statistics.). They also frequently prescribed for treating anxiety disorders, eating disorders (such as bulimia, anorexia), obsessive-compulsive disorders, smoking cessation, chronic pain syndrome and hormone-related disorders, such as severe menstrual cramp.

There are many different types of antidepressants, including selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, monoamine oxidase inhibitors (MAOIs), dopamine antagonists and lithium, among others.

Tiredness and extreme fatigue is a common side effect of this class of drug, especially during the early weeks of treatment. Antidepressants cause tiredness through their physiological effect on the brain chemicals called neurotransmitters, mainly norepinephrine and serotonin and on adrenal hormones.

For most people, the side effects of antidepressants wear off as their bodies become acclimatized to the medication. If after several weeks you’re still feeling tired, consult with your doctor or another healthcare provider about adjusting your dosage since drug side effects are dose-related. You might also want to explore other drugs, especially if you are on one of the tricyclic antidepressants which are considered unsafe for older people. Also, stay clear of alcohol and any medications that also tend to be sedating. Combining them with your antidepressants could make your fatigue worse.

Commonly prescribed antidepressants include duloxetine (Cymbalta), fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft) and venlafaxine (Effexor).



Antihistamines are used to prevent or relieve symptoms associated with allergic reactions such as the hay fever, wheezing or the common cold. Some antihistamines are also used to treat anxiety and insomnia, nausea and vomiting and to prevent motion sickness.

Common side effects of antihistamines include weakness, drowsiness, tiredness, and sleepiness.

Newer-generation antihistamines such as loratadine (Claritin) and cetirizine (Zyrtec) are better tolerated by older patients and present a lower risk for fatigue. Other popular antihistamines include diphenhydramine, brompheniramine (Bromfed, Dimetapp), hydroxyzine (Vistaril, Atarax), and meclizine (Antivert).

Hypertensive Drugs


Many people find that their blood pressure medications seem to make them feel more fatigued, tired, and low in energy.

There are at least eight categories of drugs that help control hypertension and each of them functions differently. Anti-hypertensive medications may slow down the contractile action of the heart as well as depress the entire central nervous system, or, in the case of diuretics, deplete electrolytes that the body needs, causing your body to excrete large volume of water and sodium

Popular blood-pressure medications include lisinopril (Prinivil, Zestril), an ACE inhibitor; Amlodipine (Norvasc), a calcium channel blocker; Hydrochlorothiazide (HCTZ and various other brand names), a Thiazide diuretic; Furosemide (Lasix), a loop diuretic; and Metoprolol (Lopressor, Toprol), a beta blocker. Fatigue is also one of the most common side effects that occur with Aliskiren (Tekturna, Tekturna HCT), which belongs to a newer class of drugs called renin inhibitors.

Talk with your doctor or another healthcare provider about switching to another type of blood pressure medication. For older patients, a benzothiazepine calcium channel blocker, such as diltiazem (Cardizem), may be a good alternative.


Anti-anxiety Drugs


Commonly known as tranquilizers, are used for a variety of anxiety disorders such as phobias, panic disorder, generalized anxiety disorder and post-traumatic stress disorder

Benzodiazepines are among the most widely prescribed medications for treating anxiety disorders. They are also used to prevent seizures, muscle spasms, agitation and muscle spasms. These drugs bind to a receptor in the brain that releases a chemical called GABA. When GABA is released, it signals the brain and body to relax, which can provide short-term relief to someone with intense anxiety.

People who take a benzodiazepine for more than two or three weeks may develop a tolerance to the drug, and over time may need to take increasing doses to achieve the same effect, only worsening their fatigue.

Older people are at a much higher risk for experiencing extreme fatigue and for developing psychological dependence for prolonged benzodiazepine use.

Commonly prescribed benzodiazepines include alprazolam (Xanax), clonazepam (Klonopin), diazepam (Valium), lorazepam (Ativan) and temazepam (Restoril).

Patients with mild anxiety do not need benzodiazepines at all. Withdrawal symptoms can occur if the dosage is suddenly discontinued or reduced. This should be strictly monitored by a professional.




Hallucinogen is any substance that distorts a person’s sense of reality. When they are taken in large doses, they result in hallucinations and delusions. They cause a scrambling effect on the brain, subjecting the patient to an emotional rollercoaster. These mood swings can bring about sleepiness, fatigue, insomnia, memory loss, violence or suicide. Marijuana is a very common hallucinogen.


Statins and Fibrates


These group of anti-lipidemic medications is used to treat high cholesterol in the blood. Stains disrupt the production of energy in cells. They also stop the production of satellite cells that generate muscle tissue, resulting in the rapid breakdown of skeletal muscles, muscle weakness, fatigue and severe muscle aches throughout the body. Myoglobin, a by-product of muscle breakdown can result in severe kidney damage and even kidney failure.

The top-selling statins are atorvastatin (Lipitor), rosuvastatin (Crestor) and simvastatin (Zocor); the top-selling fibrate is fenofibrate (Tricor).

Cancer Treatment


Common side effects of all kinds of cancer medications are fatigue and tiredness. As these drugs kill cancer cells, they also destroy and damage normal cells in the body. In an effort to clean and fix up the cells, the body expends extra energy, causing the [patient to feel very weak




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