I believe that Castor oil is safer for short term use for constipation relief than Mineral Oil but neither one should be used for more than 7 days.  

Castor oil has been used medically for thousands of years.  There is evidence of it being used by Ancient Egyptians.  Generations of mothers have used Castor oil for constipation relief for their families.  When something has been used for thousands of years, it generally shows that it is safe and effective.  You can take Castor oil internally for immediate constipation relief or use a Castor oil pack as a constipation remedy.