antibioticsbooks

254 PART 5 Antiviral Drugs
Adverse Effects
These agents are all very well-tolerated by most
patients and have a low incidence of adverse effects.
Fatigue and elevations in creatinine phosphokinase
are possible, though the latter may be associated
with HBV itself. Lactic acidosis is uncommon.
■■
Important Facts
• All of these drugs have some activity against
HIV, though the doses that are required to
treat HIV infection are higher than the HBV
doses. Using them at the lower HBV doses
in a co-infected patient can select for mutant
viruses that are resistant to NRTIs and this
should be avoided. Patients with known HBV
should be tested for HIV before therapy is
started with one of these drugs.
• Whenever a drug that is active in both HIV
and HBV is used, like lamivudine or tenofovir
(both NRTIs), it should be given in the higher
HIV dose.
What They’re Good For
These are drugs-of-choice for chronic HBV infection.
They do not cure the infection, but can repress
it to the point that it does not progress.
Don’t Forget!
Be sure your patient is not co-infected with HIV
before treating HBV with one of these drugs.