Q: I am a 25-year-old female, and for the past five years I am suffering from chronic kidney disease with creatinine 3.9 mg/dl and blood urea 87 mg/dl. I had taken three doses of Hepatitis B (Engerix B - 20 microgram, one on each arm) last year. I was supposed to take my fourth and final dose ten months back, which I missed. What should I do now?

A:There are two basic schedules of vaccination for Hepatitis B (Engerix B 20mcg) in adults: 0-1-6 months plus a booster dose at 12 months (optional in most cases, except certain people at increased risk such as HIV positive, etc.) or the accelerated schedules, i.e. 0-1-2 months or 0-7 days -21 days. You have followed 0-1-2 months schedule. A booster dose can be taken, if required at all, 12 months or even five years from the first dose.