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Side effects on the 10 most commonly prescribed medications


A side-effect is a disturbing feeling or a sign that is caused due to the ingestion of a medication or during medical treatment. These side effects can occur due to all kinds of medicines, including the prescription and over-the-counter drugs, as well as the complementary medication such as herbal preparations.

Here is a brief discussion about the 10 most commonly prescribed medications and the side effects caused by them. We will also have a look at the various natural ways that are effective in minimizing the risk of these side effects.

1. Atorvastatin - Lipitor 

The unhealthy lifestyle followed by a large percentage of people across the world has led to a sharp rise in the incidence of hypercholesterolemia. Hence, there is also an increase in the use of cholesterol-lowering drugs such as atorvastatin. Though the efficacy of this drug for reducing lipid levels has been confirmed through several research studies, some studies have proved the toxic effects caused by the same on different organs of the body including the liver, kidneys, heart and the eyes.

It may affect the functions of the kidneys leading to dark colored urine or increased frequency of urination. [1]
There is evidence to prove that the use of statins like atorvastatin may lead to mitochondrial dysfunctions. It may also cause cognitive loss, neuropathy, and sexual dysfunction. [2]

The risk of rhabdomyolysis or myopathy is also higher following the use of this drug. The higher dose of this drug may also lead to proteinuria and hematuria. [3] There have been cases reported of patients developing pancreatitis due to the use of Atorvastatin. [4]

Atorvastatin therapy is also associated with asymptomatic, serum aminotransferase elevations. It has been found to affect the liver functions. The clinical presentation of the atorvastatin induced hepatotoxicity varies from simple cholestatic hepatitis, to hepatocellular injury. [5] The ocular side effects of this medication are blurring of vision and visual impairment. [6]

2. Amlodipine - Norvasc

Amlodipine is one of the most commonly prescribed drugs to the patients diagnosed with hypertension. It may lead to some mild side effects such as extreme sleepiness, pain in the stomach, and dizziness. [7] It may affect the functions of the kidneys and cause swelling of the legs or ankles. [8]

However, since hypertension is a chronic disorder, patients have to take this medication for a prolonged duration. Patients may develop side effects due to the long-term use of Amlodipine including arrhythmia and tachycardia. Flushing, headache, and dizziness were also reported by the patients taking Amlodipine. [9]
Also, since Amlodipine is processed in the liver, it may increase the risk of hepatic disorders. Amlodipine can affect the functions of the heart and increase the risk of myocardial infarction.

Some of the side effects are attributed to the vasodilatory property of this drug. It can lead to palpitations, and peripheral edema. [10] In some cases, the anti-hypertensive effect of this medication may lead to sudden hypotension resulting in fainting. It can also increase the cholesterol levels. The use of amlodipine may also increase the risk of gingivitis and gingival enlargement. [11]

3. Alprazolam - Niravam

Alprazolam is a commonly prescribed antidepressant medication. It has also been approved for the management of anxiety and panic disorders. The widespread use of benzodiazepines like alprazolam has led to the recognition of their side effects. A study has found that this drug may cause sedation, irritability, unexplained weight loss, and ataxia. The risk of enuresis, aggression, and disinhibition is also higher in the patients who use Alprazolam for a longer duration. [12]

Some patients may develop an allergic reaction to Alprazolam resulting in itching, trouble breathing, hives, and swelling of the face along with a sensation of tingling in the mouth. [13] One scientific study has confirmed that the chronic use of Alprazolam may affect psychomotor and attentive performance. [14]

However, the most dangerous side effect of this drug is the impairment in the levels of alertness. It can reduce the ability of a person to concentrate and stay alert. Hence, patients are strictly warned against driving or working with heavy machinery while taking treatment with Alprazolam. [15] Research has indicated that Alprazolam may cause memory impairments that may persist even after the medication is withdrawn. [16]

4. Methylphenidate - Ritalin 

Methylphenidate is a central nervous system stimulant. It is used to treat the children and assaults suffering from ADHD (Attention Deficit Hyperactivity Disorders). It affects the balance of chemicals in the brain and nervous system that contribute to the symptoms of ADHD such as hyperactivity, agitation, and impulse control.
However, there is a serious warning about the inadvertent use of this drug. The Drug Enforcement Administration has classified it as a Schedule II drug, which means it has a high potential for drug abuse.
Addiction to Ritalin can occur when a user takes it without proper medical supervision or in excess of the recommended parameters. Patients, who abuse Ritalin, usually take it for losing weight, staying alert or awake, or to get a “high.” [17]

It is commonly used by students and working professionals to give a boost to their mental powers. Ritalin works similar to cocaine and any stimulant and provides a false perception of wellness or “high” that is inevitably followed by a “crash,” and a feeling of extreme fatigue, depression, and reduces alertness.
They tend to develop a resistance to the lower doses of Ritalin and hence, have to resort to taking the higher doses of the same drug or even cocaine to derive the same effect. Over a period of time, this results in a dependency on Ritalin and cocaine. [18]

Ritalin only masks the feeling of tiredness or depression for the time being. When the “high” fades away, the unwanted feeling or condition returns with a higher intensity, which forces the user to turn to the stronger drugs as Ritalin does to work any longer. [19] Other than dependency, Ritalin may also cause other side effects such as insomnia, headache, stomachache, and anorexia. [20] It may also cause loss of self-confidence, reduced appetite, and dizziness. [21]

5. Amoxicillin - Amoxil 

Amoxicillin is a penicillin-group of antibiotics that has been in use for treating infections since the 1970s. This drug is used to treat the bacterial infections such as pneumonia and bronchitis. Though this drug is on the WHO's list of the most essential medicines, it is also known to cause several side effects. It may cause allergic reaction, blistering, and peeling of the skin. Some patients develop digestive disturbances resulting in loose motions along with blood in stools, stomach cramps, and fever. [22]

Though most acute respiratory infections can be managed well with the help of Amoxicillin, inevitable consequences may occur due to its injudicious use. It leads to the development of new drug resistance strains of the infective organism due to which the patients may fail to respond favorably to the drug for the management of infections.

The harms caused due to the antibiotic resistance cannot be quantified. Yet, it is highly important to avoid it. The incidence of antibiotic resistance to Amoxicillin can be controlled by using this drug judiciously and avoiding its prescription in the cases of viral and fungal infections. [23] Amoxicillin has been found to affect the meninges and cause Meningitis. Meningitis usually occurs following an infection due to bacteria or viruses. But, some patients may develop drug-induced aseptic meningitis following the use of amoxicillin.

Patients may develop the typical symptoms of meningitis such as fever, severe headache, and neck stiffness. [24] The postoperative administration of this drug can cause an increase in the number of resistant anaerobes. It can also reduce the number of sensitive Gram-positive cocci. [25] Some other side effects of Amoxicillin include nausea, vomiting, vaginal itching, and a black, swollen, or "hairy" tongue. [26]

6. Metformin - Glucophage 

Diabetes is another common lifestyle disorder that has seen a sharp rise in its incidence across the world. Metformin is commonly prescribed to the patients diagnosed with this condition. It is prescribed to the patients suffering from type 2 diabetes to regulate the blood sugar levels.

A regular use of Metformin may cause a serious complication called lactic acidosis. Patients may develop dizziness, drowsiness, tiredness, muscle pain, coldness of the skin, and difficulty in breathing. [27]
The use of Metformin in higher doses or in combination with other anti-diabetic drugs may result in Hypoglycemia. [28] About 25% of the patients may experience metformin-associated gastrointestinal side-effects such as abdominal pain, flatulence, and nausea. [29]

Metformin can also affect the uptake of glucose, and vitamin B12. In the colon, it can modify the glucose cell metabolism. It may also cause the stimulation of the intestinal secretion of serotonin, and cause changes in the incretin metabolism. [30] The incidence of acute pancreatitis is also higher in the patient using metformin. [31] Treatment with Metformin is associated with a higher incidence of the loose motions. [32]

7. Gabapentin - Neurontin 

Gabapentin is one of the most commonly prescribed medications for the patients suffering from seizures. It is also prescribed to treat nerve pain. Some patients may develop a mild allergic reaction to this medication.

The symptoms of the allergic reaction include itching, hives, swelling of the face or hands, and trouble breathing. [33] Some other side effects of gabapentin include aggression, restlessness, moodiness, and trouble concentrating. These symptoms are more common in children. It may affect their motor and cognitive functions. [34]

Some patients may experience dizziness, excessive sleepiness, an unsteady gait, and water retention. [35]
Hepatotoxicity is a rare side effect of gabapentin. The latency period for the onset of this side effect ranges between 1 and 8 weeks. It is often associated with the cholestatic pattern of elevations in the enzymes. [36] Gabapentin may also cause psychotic, ataxia, sedation, and depressive symptoms. [37]

8. Lisinopril - Prinivil

Lisinopril belongs to the class of drugs called the ACE inhibitors. It is used for the treatment of hypertension and congestive heart failure. This drug may cause a few adverse effects like changes in the amount and frequency of urination. It may also lead to confusion, severe weakness, and an uneven heartbeat, along with trouble breathing, lightheadedness, and even fainting. [38] This drug can have an adverse effect on the patients' quality of life by affecting the emotional, social, and cognitive functions. [39]

Lisinopril, when used alone and in combination with rosuvastatin, can decrease the hemoglobin level, and hematocrit. It can also cause an increase in the total white blood cells, absolute lymphocyte, and neutrophil counts. It has been found to affect the liver functions as is evident from the raised serum levels of alkaline phosphatase (ALP), aspartate aminotransferase (AST), and total bilirubin. [40]

Some rare side effects of Lisinopril include a feeling of suffocation and dry cough. [41] Prinivil may sometimes interact with other medications such as the antihypertensive drugs, blood lithium, and potassium supplements resulting in side effects. [42]

9. Levothyroxine – Synthroid

Levothyroxine helps in the management of thyroid diseases such as hypothyroidism. It can stimulate the production of thyroid hormones and thus, regulates the metabolism. However, the use of this drug over a longer duration may lead to the development of a few side effects including irregular heartbeat, seizures, blurred vision, and double vision. [43] It can also affect the on hemostasis and biochemical parameters. Research has shown that it can cause disturbances in the coagulation system. [44]

The use of levothyroxine can also reduce the bone mineral density. It may cause peripheral bone loss. This side effect is more common and severe in the postmenopausal women. [45] This drug can also affect the mood, and cognitive functions of the patients. It can reduce their declarative memory, working memory, and motor learning abilities. [46] Some patients may develop levothyroxine-induced liver dysfunctions causing abnormalities in the levels of liver enzymes. [47]

10. Prednisone - Deltasone

Prednisone is a form of steroids that was discovered in the 1950s. It is used as an immunosuppressant medication to relieve the symptoms of some forms of cancer, allergic disorders, and autoimmune diseases such as rheumatoid arthritis.

The adverse effects associated with the use of prednisone in the treatment of oral inflammatory ulcerative diseases has proven that it can cause severe bloating, and insomnia. [48] A comparative study of the beneficial effects and side effects of prednisone has shown that this drug may cause an inhibition of the hypophysis. It may influence the body weight, and produce an ulcerogenic effect. It has been found to be responsible for causing sodium retention and stimulating the catabolic, and diabetogenic processes in the body. [49]

The use of this medication is also associated with a risk of osteoporosis, hyperglycemia, adrenal suppression, dyslipidemia, Cushing’s syndrome, immunosuppression, and psychiatric disturbances. [50]
A prolonged use of steroids like prednisolone in children can result in growth retardation. It may also inhibit the natural wound repair processes and cause metabolic disturbances. It can increase the risk of glaucoma, and cataracts. [51] Patients may develop the symptoms of mania, hypomania, depression, and psychosis during and after the corticosteroid therapy with prednisolone. [52] The other common side effects of prednisolone include gastrointestinal disturbances, polyuria, mood alterations, and insomnia. [53]

Writer: Dr. Jyothi Shenoy



Topics: medications

Dr Mohamed Abdel Hamid

Written by Dr Mohamed Abdel Hamid

Dr. Mohamed Abdel Hamid is a practicing dentist, the founder and owner of confidential clinic in Cairo, Egypt. He graduated from the faculty of dentistry, Ain Shams University, obtaining his Bachelor of Dental Surgery (BDS) in 2010 and has been practicing ever since. He acquired a postgraduate diploma of Oral Surgery in 2013 from the same university. In 2014, he acquired the membership of faculty of dental surgery (MFDS) from the Royal College of Surgeons of Edinburgh (RCSEd), one of the highest honors in professional dentistry. In 2016, He became a member of the American Academy of Cosmetic Dentistry (AACD), the highest recognized institution in the world pertaining to cosmetic dentistry and beauty.