Ranjbar et al. is the main treatment strategy in co-infection whereas two effective agents should be selected against HBV infection. Because antiviral resistance is a probability in treatment, choosing active agents seems complicat- ed, that is the choices for treatment of HBV infection are limited by resistance to HIV therapy. The first aim of therapy is to decrease the amount of HBV DNA to an undetectable level; so using less potent agents is not an option. The most potent agent such as tenofovir plus lamivudine or tenofovir plus emtricita- bine is recommended as the best choice (Figure 1).55,56 In a study performed by GERMIVIC Study Group, Piroth et al. reported that lamivudine monotherapy was a very common and a first-line treatment. Other treatment methods included in their study were tenofovir along with lamivudine or emtricitabine, and tenofovir alone.60 One of the important implications in the treatment of HBV-HIV co-infection was that the dosages of different medications being applied should be adjusted to HBV condition. Conclusion According to the data acquired from different sources and authorities, it is comprehended that HBV/HIV co-infection rate might grow if appropriate control- ling mechanisms are not considered. Epidemiological investigations are needed to be performed, so that atypical transmission routes and high risk locations and environment would be identified. Researches in behavior are also necessary in case of further under- standing of failures and not effective treatments. Moreover, observation systems seem necessary to monitor infection patterns to target high prevalence regions. To define upper limit of HBV DNA level, clinical studies are needed to be performed for the on- set of treatment in both liver disease and co-infection. Finally, recent research showed expanded access to proper treatment methods that can help to reduce the morbidity and mortality rate in HIV- or HBV- infec- tions and also in co-infections, mostly by lowering the viral load among individuals and communities. Conflict of interest: None declared. WWW.ircmj.com Vol 13 December 2011 References 1 860 Fig. 1: Medications used for treatment of chronic hepatitis B virus (HBV). The arrow refers to medication to use when treatment of both HBV and HIV is considred.59 Alavian SM. Hepatitis B virus infection in Iran; Changing the epidemiology. Iran J Clin Infect Dis 2 2010;5:51-61. Devi Kh S, Singh NB, Singh HL, Singh YM. Coinfection by human immunodeficiency virus, hepatitis B virus and hepatitis C virus in injecting drug users. J Indian Med Assoc