Introduction:
Drug-induced liver diseases result due to the intake of certain medications beyond the recommended time. The medications prescribed by a doctor or over-the-counter medications (medications that do not need a prescription), vitamins, herbal medicines, hormones, and illicit or recreational drugs can cause damage to the liver and cause liver disease. Medications containing Acetaminophen mainly cause drug-induced liver disease over a long period.
Certain medications cause an elevation in the levels of liver enzymes in the blood and result in liver cell damage. The function of the liver is to convert the harmful (toxins) substances in the blood to harmless substances and remove them from the body. These toxins are released into the blood during the processing of medications and alcohol. When the liver does not remove the toxins, they cause damage to the liver cells resulting in liver disease.
The liver becomes red and swollen. There are no specific symptoms of drug-induced liver disease, but they show symptoms similar to any liver disease. The symptoms are pain in the stomach (abdomen), jaundice, tiredness, dark-colored urine, prone to infections, swelling in the legs, abdominal enlargement, fever, vomiting, pale-colored stools, and gastrointestinal bleeding. The drug-induced liver disease, like any other liver disease, is ruled out by undergoing certain blood tests. The tests include liver function tests, complete blood count, antinuclear antibody (ANA) test, and an electrolyte panel. Some imaging techniques like an ultrasound of the abdomen, CT (computed tomography) scan, MRI (magnetic resonance imaging), and liver biopsy also help detect liver disease. The treatment is to stop taking the medication that causes liver damage.
What Are the Types of Drug-Induced Liver Disease?
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Hepatitis: Swelling or inflammation of the liver.
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Hepatocellular Necrosis: Severe hepatitis causes the death of liver cells (necrosis).
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Cholestasis: Reduced bile secretion or decreased flow of bile due to blockage in the liver.
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Steatosis: Excess fat deposition in the liver.
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Cirrhosis: Cirrhosis is scarring of the liver. Healthy liver cells are replaced by scar tissue. This hardens the liver and does not function properly.
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Mixed Disease: A combination of diseases occurs in mixed hepatic disease, like hepatitis and necrosis of the liver, hepatitis and steatosis, and hepatitis and cholestasis.
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Fulminant Hepatitis: A very rare type of severe form of liver disease that occurs within a few days or weeks of the start of liver inflammation. It causes huge damage to liver cells, resulting in the death of liver cells, and the size of the liver is also reduced. In addition, the functions of the liver are affected and result in hepatic coma.
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Hepatic Vein Thrombosis: Formation of a blood clot in the veins of the liver. This causes a block in the veins of the liver, causing a backflow of blood to the heart. This deprives the liver of pure or oxygenated blood for normal functioning. This leads to liver damage and liver disease.
What Are the Symptoms of Drug-Induced Liver Disease?
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Abdominal pain.
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Jaundice (yellowish discoloration of the skin and eyes due to excess bilirubin in the blood).
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Ascites (abdominal enlargement due to fluid accumulation).
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Loss of appetite.
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Tiredness.
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Gastrointestinal bleeding.
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Nausea and vomiting.
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Swelling of the legs due to fluid accumulation (pedal edema).
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Fever.
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Dark-colored urine.
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Pale-colored stool.
How Is a Drug-Induced Liver Disease Caused?
It is caused by taking any of the below-mentioned medications beyond the recommended time or dosage. These medications damage the liver cells causing improper functioning of the liver.
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Acetaminophen: These are antipyretic (which reduces the body temperature during fever) and painkiller medications for mild to medium pain. This damages the liver cells directly and causes an increase in the liver enzymes in the blood.
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Anabolic Steroids: Anabolic steroids are medications given to men with hormonal problems like late puberty and to improve muscle mass. There is muscle loss in certain disease conditions; to improve muscle build-up, steroids are given. Some athletes or bodybuilders misuse these medications for bodybuilding. Unfortunately, these medications, when used beyond the recommended time, cause liver damage.
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Antibiotics: Antibiotics are medications given to treat bacterial infections.
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Oral Contraceptives: Birth control pills are available over-the-counter and do not need a prescription. The combination of estrogen and progesterone cause cholestasis (decreased flow of bile). Though the reasons are unclear, this results in damage to the liver cells.
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Statins: Statins are medications that lower cholesterol levels. They block the liver from producing cholesterol. They cause liver enzymes to seep into the bloodstream, causing increased levels of liver enzymes. They rarely cause severe liver damage.
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Anti-epileptic Drugs: These medications are used in the treatment of seizure patients. These medications increase the level of liver enzymes, thus causing damage to liver cells.
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Non-steroidal Anti-inflammatory Drugs (NSAIDs): NSAIDs are medications given for bone and joint problems to reduce swelling. When they are taken beyond the recommended period, they cause liver damage. Medications like Ibuprofen, Aspirin, and Indomethacin are examples of NSAIDs.
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Herbal Medicines: Natural medicines like Ephedra, Germander, and Pennyroyal cause liver damage. Ephedra is a Chinese herbal medicine used to treat lung disease. It is a neurotoxin that damages the nervous system. When taken for more than three months, it causes symptoms of liver damage and nervous system damage. Germander is used as a flavoring agent. It is a highly toxic agent which causes severe liver damage and death. Pennyroyal is a herb used for pneumonia, common cold, and abortion, and also used as an insect repellent. Pennyroyal is a harmful herb, and consuming a small dose can cause damage to intestinal walls and liver cells.
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Vitamins: Taking vitamin A for years and taking higher doses of vitamin A causes liver disease by increasing the levels of liver enzymes.
Who Is at Risk for Drug-Induced Liver Disease?
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People who already have liver disease.
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Older adults.
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Females.
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People who consume alcohol.
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People who have HIV infection (human influenza virus).
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People who take extended-release medications (the action of the medication starts slowly).
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People who take medications that contain Acetaminophen frequently.
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Taking herbal medicines.
How Is a Drug-Induced Liver Disease Found?
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History of Medication: A detailed history of the medications consumed by the patient should be asked.
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Liver Function Tests: Liver function tests are a group of tests that include the screening of liver enzymes, proteins, and prothrombin time. Liver enzymes like alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transaminase (GGT), and proteins like albumin and globulin are screened for diagnosing liver disease. The changes in the normal values of these enzymes and proteins suggest liver disease.
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Prothrombin Time: Test to check for normal clotting (thickening) of blood. Delayed clotting time reveals underlying liver disease.
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Complete Blood Count: Complete blood count (CBC) is done to check variations in the components of the blood, like red blood cells (RBC), white blood cells (WBC), platelets, and hemoglobin.
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Antinuclear Antibody Test (AAT): Antinuclear antibody test is done to detect antinuclear antibodies. This antinuclear antibody is present when there is an autoimmune (when the body’s immune system attacks its healthy organs) reaction. Therefore, this test is done to find out autoimmune diseases.
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Electrolyte Panel: This test is done to check the fluid electrolyte (mineral present in the blood and other body fluids) balance in the body. If there are changes in the levels of the electrolytes, there will be an electrolyte imbalance. This helps find out about liver disease and other organ diseases.
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Ultrasound: An imaging technique that uses high-frequency sound waves to capture images of the internal organs and structures to find any abnormalities.
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CT Scan: This computerized tomography test uses a computer to control the X-ray source. Images of the internal organs and internal structures are captured from various angles. This gives a detailed view of the organ to be detected for any abnormalities.
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MRI Scan: MRI scan uses a combination of strong magnetic fields and radio waves to capture images of the internal organs and structures. This test gives more detailed information about the targeted structure.
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Liver Biopsy: Liver biopsy involves the removal of a tiny portion of liver tissue to view pathological changes in a microscopic view. This is a confirmatory test and reveals the type of liver disease.
How Is Drug-Induced Liver Disease Treated?
The treatment of drug-induced liver disease is finding the drug that causes the damage and stopping it. Most conditions in drug-induced liver disease are reversible. The liver regenerates (repairs and forms new cells) on its own. In some cases of Acetaminophen overdose, N-acetylcysteine is administered to prevent liver damage and failure. A liver transplant will be recommended for acute liver damage.
What Is the Prognosis of Drug-Induced Liver Disease?
The prognosis for this liver disease is good as the condition is reversed after stopping the medication. However, the prognosis will be poor in severe cases like irreversible liver damage or liver failure.
What Are the Complications of Drug-Induced Liver Disease?
If the medications are not stopped, there will be irreversible damage to the liver resulting in liver failure.
How to Prevent Drug-Induced Liver Disease?
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The drug-induced liver disease can be prevented by taking the right dosage of medications for the prescribed time only.
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Avoid natural or herbal remedies. They are not always safe.
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Discuss the possible side effects of over-the-counter medications with the doctor before taking a medicine.
Conclusion:
Drug-induced liver diseases can be prevented by consuming medications for the recommended time only. Though this disease is not serious, stopping the medications help overcome the symptoms to lead a healthy life.
