if (ViewBag.CurrentFilter != null)
    {
        string[] ids = new string[ViewBag.CurrentFilter.Length];
        int i = 0;

        foreach (string id in ViewBag.CurrentFilter)
        {
            ids[i] = id;
            i++;
        }

        @Html.PagedListPager(Model, page => Url.Action("Index") + "?" + string.Join(",", ids.Select(x => "AllergyID=" + x)) + "&" + page);


    }
    else
    {
        @Html.PagedListPager(Model, page => Url.Action("Index", new { page = page }));
    }