Liver drugs (encephalopathy, varices, paracetamol)
also: lactulose · rifaximin · terlipressin · spironolactone ascites · N-acetylcysteine
Overview
The drug decisions in decompensated liver disease and paracetamol overdose — encephalopathy, variceal bleeding, ascites, SBP and the NAC antidote.
Mechanism
Lactulose acidifies the colon → traps ammonia as ammonium (↓absorption); rifaximin is a non-absorbed gut antibiotic (↓ammonia-producing bacteria). Terlipressin is a vasopressin analogue → splanchnic vasoconstriction (↓portal/variceal pressure). Non-selective β-blockers (propranolol/carvedilol) lower portal pressure (variceal prophylaxis). Spironolactone (± furosemide) treats ascites. N-acetylcysteine replenishes glutathione (paracetamol).
Indications
- Hepatic encephalopathy
- Variceal bleeding + prophylaxis
- Ascites
- Spontaneous bacterial peritonitis
- Paracetamol overdose
The agents
Lactulose titrated to 2–3 soft stools/day; rifaximin for recurrence prevention.
IV
Plus endoscopic band ligation; antibiotics (e.g. ceftriaxone) reduce mortality.
Non-selective β-blocker lowers portal pressure.
Aldosterone antagonist first-line for ascites (cross-ref CV MRA).
IV
Per nomogram / staggered-OD criteria; anaphylactoid reaction → slow infusion.
Spontaneous bacterial peritonitis (neutrophils >250); + norfloxacin prophylaxis.
Adverse effects
Slow/stop infusion, antihistamine, restart slower.
Cautions & contraindications
Hepatotoxicity is time-dependent.
Interactions
- —
Monitoring & kinetics
Encephalopathy grade/stools; ascites: weight, U&E; paracetamol: INR/ALT/creatinine (King's College criteria)
Mixed oral/IV. See the antidote tool for the full overdose set.
Source: NICE — Cirrhosis / variceal bleeding · BNF — Liver