| Liver is a large reddish-brown glandular | | | | These include, but are not limited to: |
| organ located in the upper right portion of | | | | |
| the abdominal cavity behind the rib cage. It | | | | Hepatitis: Certain drugs can cause acute and |
| secretes bile and functions in metabolism of | | | | chronic hepatitis (inflammation of liver |
| proteins, carbohydrates and fats. It is known | | | | cells) that can lead to necrosis i.e. cell |
| to produce various factors involved in the | | | | death. Acute drug-induced hepatitis lasts |
| clotting of the blood & synthesize vitamin A. | | | | less than 3 months, while chronic hepatitis |
| Liver also breaks down worn-out erythrocytes | | | | lasts longer than 3 months. Some drugs that |
| (RBCs). As most of the chemical compounds, | | | | cause acute and chronic hepatitis include |
| whether taken orally or injected | | | | phenytoin, diclophenac, & nitrofurantoin. |
| intravenously, are taken to liver, the | | | | |
| majority of small-molecule drug metabolism is | | | | Fulminant hepatitis: Rarely, drugs cause |
| carried out in the liver by cytochrome P450 | | | | acute liver failure or fulminant (sudden & |
| which are membrane bound oxidative enzymes | | | | severe) hepatitis. These patients are |
| which metabolize various endogenous and | | | | extremely ill with the symptoms of acute |
| exogenous molecules. | | | | hepatitis. |
| | | | |
| Action of drugs: Drugs can lead to liver | | | | Cholestasis: It is a condition in which the |
| disorders in several ways. Some drugs are | | | | secretion and/ or flow of bile is reduced. |
| directly deleterious to the liver while | | | | Example- erythromycin, chlorpromazine etc. |
| others are transformed or metabolized by | | | | |
| liver into chemicals that can cause liver | | | | Mild elevations in blood liver enzyme levels: |
| damage either directly or indirectly. | | | | Many drugs cause mild elevations in blood |
| | | | levels of liver enzymes, often without any |
| Dose-dependent toxicity: It occurs when any | | | | major symptoms. For example, statins & some |
| given drug is taken in excess, the increased | | | | antidepressants are known to increase levels |
| concentration of that drug or its metabolite | | | | of liver enzymes in blood. |
| may lead to liver damage. Such drugs are | | | | |
| usually harmless if taken within prescribed | | | | Necrosis: Blood clotting in the liver veins |
| limits. For example, acetaminophen overdose | | | | may cause death of liver cells. For example, |
| is known to cause dose-dependent toxicity in | | | | Pyrrolizidine alkaloids can cause blood |
| liver. | | | | clotting. |
| | | | |
| Idiosyncratic toxicity: Drugs that cause | | | | Cirrhosis: It is a chronic disease |
| idiosyncratic toxicity cause disease in only | | | | interfering with the normal functioning of |
| those few individuals who have inherited | | | | the liver due to scarring. Drugs like |
| specific genes that are associated in some | | | | amiodarone and methyldopa may lead to |
| way to the chemical transformation of that | | | | Cirrhosis. |
| particular drug. | | | | |
| | | | Diagnosis: Diagnosis of liver disorders is |
| Drug allergy: It occurs when a drug or its | | | | based on a patient's symptoms, which may vary |
| metabolite acts as an allergen which may | | | | from loss of appetite, nausea, fatigue, |
| initiate hypersensitivity reaction by the | | | | itching, dark urine, to jaundice, enlarged |
| body's immune system leading to local | | | | liver etc. Laboratory testing may also be |
| inflammation that may damage liver tissues. | | | | used to detect blood liver enzymes levels, |
| | | | bilirubin levels which may suggest abnormal |
| Drug induced liver diseases: Various | | | | liver behavior. An unusually long blood |
| exogenous drugs and endogenous chemicals can | | | | clotting time may also be an indicative of a |
| cause a wide spectrum of liver injuries. | | | | potential liver damage. |