Identification

• Brachytherapy or seed therapy is a cancer treatment that uses small radioactive pellets inserted directly into the prostate to destroy cancer cells. Like other forms of prostate cancer treatment, seed therapy causes some side effects.
  
  

Types of Side Effects

• The side effects of seed therapy come in two distinct stages. The first stage is due to the procedure of insertion, and the second occurs because of the radiation itself.
  
  

Time Frame

• First-stage side effects typically develop within the first few hours after treatment and persist for up to two weeks. The second stage begins within a month after treatment and continues for three to nine months, according to the Radiation Medical Group.
  
  

Stage 1 Side Effects

• Side effects possible during Stage 1 include blood in urine or semen, anal irritation, hemorrhoids and pain in your pelvis or penis. Urinary urgency is also common during this stage, and as many as 10 percent of men develop a blockage that prohibits urination for up to seven days.
  
  

Stage 2 Side Effects

• Sexual side effects typically develop during the second stage of seed therapy with impotence and reduced semen as common features. At times, urinary frequency develops late in Stage 2.
  
  

Risks

• Seed therapy has the potential to cause infertility. Rarely, a seed used in brachytherapy passes through the urethra during urination or ejaculation.