While Giving My Daughter A Bath I Found Two Black

While giving my daughter a bath I found two black worms in the bottom of the tub. She has had pin worms and round worm in the past so I new to give her pinnx. After the first dose I waited to the next day to give her a bath and three moving worms came out. I sent my husband to take her to the doctor and bring the worm in a jar. The doctor sent the worm to the lab and wrote a prescription for pinn x alotgough it is over tge coubter and did not work . I called very upset to find out the doctor said this is all they can give her.