Selecting and Managing Antidepressants

Dose Adjustments
Antidepressants are metabolized through the liver, however, this does not usually mean that doses need to be reduced except in cases of severe liver dysfunction. As most patients with hepatitis C have some liver dysfunction, practitioners may want to begin at the lower dosing ranges and increase the dose slowly based on the patient's tolerance of the antidepressant. The goal should be to reach typical effective dosing ranges, as under-dosing of antidepressants is a common problem and frequently leads to non-response.

One approach to dose modification utilizes the Child-Pugh scoring system as an index of liver disease severity. A Child-Pugh score of 5 - 6 indicates normal liver function. Patients with severe cirrhosis may score as high as 15. Medications primarily metabolized by the liver should have their initial dose decreased by 25% for Child-Pugh scores of 8 or 9 and decreased 50% for patients scoring 10 or above. Medications may then be titrated upwards as clinically indicated and tolerated.

Typically, clinicians start antidepressants at lower doses, such as 50 mg of sertraline (Zoloft^®) or 20 mg of citalopram (Celexa™). Depending on the severity of the liver disease, lower starting doses may be warranted, such as 25 mg of sertraline or 10 mg of citalopram. If lower doses of antidepressants are used, quickly titrating up to typical effective doses is warranted. For example, if 25 mg of sertraline is used to start therapy, increasing the dose to 50 mg should occur after 1 - 2 weeks unless significant side effects are reported.

If the patient shows some response to a dose of antidepressant, it is prudent to wait at least another 2 - 4 weeks and reassess both clinically and with a screening instrument (e.g. BDI, Zung or other) before making any adjustments. If patients stabilize or improve, no changes are necessary, although patients should be followed at least monthly. If symptoms are unchanged or worsen, the dose can be increased.

An adequate trial of antidepressants is considered at least 4 - 6 weeks at an effective dose. If, after 6 weeks, the patient continues to worsen, he or she can be switched to another class of antidepressant medications and referred to a mental health professional.