70% of people infected with hepatitis C have chronic liver disease (long-term and progressive liver disease). This can range from mild to very severe. The severity of liver disease is an important thing to consider when prescribing medications, since for some the doses of such medications may need to be reduced, and some may need to be avoided. As a guide to the severity of liver disease, a copy of your most recent blood tests and if available a liver biopsy result, can be helpful to those prescribing any medications, including travel health practitioners.
Medications used to prevent malaria
The Advisory Committee on Malaria Prevention in UK Travellers 2002 guidelines state that nearly all anti-malarial medications tend to accumulate in the body in liver disease, and that specialist travel health advice may be necessary for safe prescribing.
Both mefloquine and doxycycline are eliminated only by the liver (not via the kidneys) so they should be avoided in severe liver disease and used with caution in milder liver disease. The most common anti-malarial medications used in mild liver disease are proguanil and chloroquine. In moderate liver impairment, proguanil tends to be prescribed. No dosage adjustment is necessary when malarone is prescribed in individuals with mild to moderate hepatic impairment.
Metronidazole
This is a useful antibiotic for treating some intestinal parasite infections (giardia or entamoeba) and is therefore sometimes given if the cause of a diarrhoeal illness is suspected or shown to be due to these infections. In severe liver disease, the daily dose should be reduced to a third of the usual and given once daily.
Vaccinations
Live Vaccines And Alpha-Interferon/Ribavirin Treatment
Vaccines are categorised as either live or inactivated. It is advised that those who are receiving either of these drugs used to treat hepatitis C should not receive live vaccines, and many also advise that live vaccines are not administered for about 3 to 6 months after completion of Alpha-Interferon/Ribavirin treatment
The following are live vaccines: measles, mumps, rubella, oral polio (the injectable polio vaccine is inactivated), oral typhoid (but typhoid injection is inactivated), BCG, yellow fever.
The following are all inactivated vaccines: diphtheria, hepatitis A, hepatitis B, meningococcal meningitis, injected polio, injected typhoid, rabies and tetanus vaccine.
