Like other drugs for HIV, Efavir works by impairing the virus's ability to multiply. However, when taken alone it may prompt the virus to become resistant. Efavir is therefore always taken with at least one other HIV medication, such as Retrovir or Crixivan. Even when used properly, it may remain effective for only a limited time..Online international store offers a EFAVIRENZ brand name without prescription. medicals products offer in our online discount pharmacy are obtained directly from USA licensed pharma manufacturers. Therefore, we guarantee quality of the EFAVIRENZ at the lowest price on the net and your satisfaction with them. Orders EFAVIRENZ are processed within 2-12 hours. Please allow 10 to 28 days for shipping. A prescription is NOT at this order .