Polycrystalline and ⟨100⟩-oriented single-crystal wires of high-purity platinum have been irradiated with 2.5-MeV electrons at ∼20 K and above liquid-nitrogen temperature. Following each irradiation, measurements of the logarithmic decrement were taken as a function of temperature. In general, the irradiations resulted in pronounced pinning and depinning effects as well as anelastic effects due to the irradiation-produced interstitials alone. The former are interpreted as, on the one hand, pinning of dislocations by interstitials which arrive at the dislocations and are immobilized, and on the other hand, the annihilation of pre-existing vacancy pinners by interstitials that become mobile on the dislocations. Aa increase in the decrement at a temperature of ∼75 K was observed in both samples, and this increase is related to the onset of interstitial pipe diffusion which brings about the mutual annihilation of the interstitial and vacancy pinners. In addition to some structure in the background, a reorientation peak attributed to anelastic reorientations of interstitial-type defects was observed at ∼38 K. The excessive width of the observed peak suggests a spectrum of activation energies associated with the peak. From the results of our experiments we assert that conclusions based upon pinning rates must take into account the possible interaction between newly arrived interstitial pinners and pre-existing vacancy pinners. These interactions will be temperature dependent and may profoundly influence low-flux, low-fluence irradiation experiments.