A topical therapeutic hydrophobic breakable composition includes a carrier comprising (a) about 60% to about 99% by weight of at least one hydrophobic oil; (b) at least one viscosity-modifying agents selected from the group consisting of a fatty alcohol, a fatty acid and a wax; and (c) a tetracycline antibiotic, characterized in that at least part of the tetracycline antibiotic is suspended in the composition; the viscosity of the composition is at least about 30% higher than the viscosity of the carrier without the tetracycline antibiotic; and is higher than the viscosity or the hydrophobic oil and the tetracycline antibiotic without the viscosity modifying agents. The tetracycline is chemically stable in the composition for at least six months; wherein more than about 90% of the tetracycline has not broken down. The composition is packaged as a breakable foam that breaks easily upon application of shear force.