Can i use a enema once every 2 weeks ?

Best not to use one at all and instead eat a diet of only whole foods and drink only water, unsweetened teas and unflavored milk. 

After your IBS clears,  you'll be happy.

After your excess fat disappears,  you'll be ecstatic. 

When you find out that you just saved your life and your children's lives,  you'll forget about winning the lottery. 

I don't think an enema once every two weeks is going to hurt anybody

You CAN use one daily. There is no good reason to do so as often as you suggest.