We consider real interpolation methods defined by means of slowly varying functions$b$and symmetric spaces$E$, for which we present extreme reiteration theorems. As an application we identify, for all possible values of$θ$∈[0,1], the interpolation spaces ($L$_{1},$L$log$L$)_{$θ$,$b$,$E$}and ($L$_{exp},$L$_{∞})_{$θ$,$b$,$E$}.