Chronic fatigue has many causes, including physical and psychological illnesses, but experts say that the side effects of many medications can also drain your energy making you feel listless.

“Medication side effects are a major hidden cause of fatigue, pain and decreased mental clarity,” Dr. Jacob Teitelbaum, author of "From Fatigued to Fantastic," tells Newsmax.

“Experience shows that numerous medication side effects contribute to chronic fatigue but virtually any prescription drug can have fatigue as a side effect. It’s worth asking your doctor if the medication can be stopped for a week to see if the tiredness goes away.”

Dr. Alexandra Sowa, a leading New York City internist, says it’s important to note that these medications do not cause the disorder known as chronic fatigue syndrome, which is an entirely different issue with its own causes and treatments.

“In my experience the following medications are the most common culprits of chronic fatigue,” she says.

Beta Blockers

Beta blockers, prescribed as the first-line treatment for high blood pressure, reduce stress on your heart by slowing your heart rate. It is this same mechanism that leaves many patients feeling fatigued and lethargic. In 2014, the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure released an update on managing blood pressure relegating beta blockers to second line treatment. Alternative treatments with drugs called thiazide-diuretics, calcium channel blockers, and angiotensin-converting enzyme inhibitors, or ACE inhibitors may have fewer side effects. If you are on a beta blocker and feeling extremely tired, ask if you can switch to another type of blood pressure medication. An omega-3 fish oil supplement may also help lower blood pressure naturally, but always check with your healthcare provider before making any changes in your medication.

Proton-Pump Inhibitors

These ubiquitous drugs used to treat gastroesophageal reflux (GERD) and other similar disorders are prescribed to 20 million Americans. Long term use of P.P.I. medications can reduce the absorption of important nutrients such as magnesium, iron, and vitamin B12. Imbalances in these levels can lead to everything from osteoporosis to anemia, which is a significant source of fatigue. The majority of patients with heart burn and acid reflex should only take a finite course of these drugs, says Dr. Sowa, and then focus on lifestyle modification, weight loss, exercise and avoiding “trigger” foods.

Antihistamines

Used to relieve the symptoms of allergies or the common cold, these drugs are central nervous system depressants. “I warn my patients that drowsiness and fatigue are major side effects of this class of medicine,” says Dr. Sowa. Traditional, “first generation” antihistamines like diphenhydramine (Benadryl) are the worst offenders. Thankfully there are “second generation” drugs like cetirizine (Zyrtec), loratadine (Claritin), and fexofenadine (Allegra) that are OK for daytime symptoms. A natural approach to easing congestion is trying nasal irrigation using a neti-pot.

Sleep Aids

You’d think that using sleep aids would relieve fatigue, but Dr. Sowa says one of the many reasons she’s against prescribing these drugs like benzodiazepine (Valium, Xanax) and zolpidem (Ambien) to treat insomnia is that they can leave you feeling exhausted during the day. They are effective sleep aids because they dampen “awake” centers in the brain. However, some of these drugs stick around in your system for extended periods of time making you tired the next day. They can also cause memory problems, dependence, and rebound insomnia. “For long term management of insomnia I recommend non-medication alternatives such as good sleep hygiene or cognitive behavior therapy which improves sleep by tackling the root of the problem,” says Sowa. Benzodiazepines used to treat depression also have the same side effects.