Drugs and Liver disease Flashcards
What are LFTs for?
measure serum levels of liver enzyme
What is ALP/GGT indicative of?
Obstructive
What is AST/ALT indicative of?
Hepatitic
What are the different phase 1 reactions
Cytochrome P450 monooxygenase system
Large family of haem protein isoenzymes
Designated CYP 450 2D6 or 3A4 etc
Large genetic difference/ environmental variation
what else happens in phase 1 reactions
increase of synthesis/decreased
breakdown of CYP isoenzymes
What happens in phase 2 reactions
conjugate almost always inactive
more polar
excreted- urine/bile
How is liver failure brought about
Increase in the AST enzymes
Hepatitis
liver failure
Give some hepatotoxic drugs
XS paracetamol Isoniazid Statins Methotrexate Amiodarone Chlorpromazine
What happens when there is XS paracetamol?
Usual conjugation pathways become overwhelmed and the remaining paracetamol is oxidised to the toxic metabolite NAPBQI
Signs of cirrhosis
Ascites Encephalopathy Coagulopathy Hepato renal syndrome Varices/portal hypertension
What is meant by ascites
The abnormal build up of fluid in the abdomen
What diuretics can by used for ascites and what does it use
Spironolactone
- blocks aldosterone receptor in distal tube
Furosemide
-loop diuretic: inhibits Na/K/Cl carrier in the luminal membrane of the loop hole
What happens in coagulopathy
Increase in prothrombin time
Treated with Vit K
Replace factors if acutely bleeding
