Embedded optical sensors always require more compact, stable, and powerful laser sources. In this Letter, we present a fully integrated passively Q-switched laser, which has been realized by a ${\mathrm{Ag}}^{+}/{\mathrm{Na}}^{+}$ ion exchange on a ${\mathrm{Nd}}^{3+}$ -doped phosphate glass. A BDN-doped cellulose acetate thick film is deposited on the waveguide, acting as an upper cladding and providing a distributed saturable absorption. At $\lambda =1054\mathrm{nm}$ , the device emits pulses of $1.3\mathrm{ns}$ FWHM with a repetition rate of $28\mathrm{kHz}$ . These performances, coupled with the $1\mathrm{kW}$ peak power, are promising for applications such as supercontinuum generation.