Hi, Doctor: I was diagnosed with ascariasis and enterobiasis in October, 2012 after a business trip to a foreign country. My doctor prescribed 200 mg of Zentel for 2 consecutive days, after 14 days I was told to repeat the same treatment-again 200mg of Zentel for 2 days. I had anaemia during and after the treatment and know I take Sorbifer by prescription of my doctor, as I still have iron deficiency . I would like to kindly ask You if it is harmless to take Zentel again without prescription now, 4 months later, because I have the same symptoms. It seems that this medicine does not help or the dosage is not correct. Could you advise which dosage and frequesncy of administration of this drug is useful for prevention of any helminths? I heard that clove oil helps also, is it effective for treatment or prevention?