**5. Conclusions**

The alpha-emitting radionuclides of 223Ra and 225Ra are a targeted alpha emitter radiopharmaceutical used to treat prostate cancer. The properties and absorbed dose value of those radiopharmaceuticals in body organs are reviewed in this chapter. Total body absorbed dose value (Gy/Bq) per intravenous injections of 223Ra was higher than 225Ac radiopharmaceuticals. This difference is related to the energy of alpha particles and the half-life of the radiopharmaceuticals. The results of this study will assist in evaluating and analyzing human body organ doses from the application of 223Ra and 225Ac that are used in mCRPC patients. The main obstacles using of 223Ra and 225Ac radiopharmaceuticals are that the daughter nuclides will always dissociate from the targeting construct upon their formation. Therefore, they can make unwanted doses in other organs.

## **Conflict of interest**

The authors declare no conflict of interest.

*Radium-223 and Actinium-225 α-Emitter Radiopharmaceuticals in Treatment… DOI: http://dx.doi.org/10.5772/intechopen.99756*
