Piperazine phosphate pentalose is an anthelmintic, mainly indicated for roundworm and pinworm infections in children. Adverse reactions to this drug are rare. Patients may occasionally experience nausea, vomiting, abdominal pain, diarrhea, headache, abnormal sensation, and hives, which will disappear soon after discontinuation of the drug. In case of allergy to piperazine phosphate, patients may experience lacrimation, runny nose, cough, dizziness, drowsiness, asthma, etc. Occasionally there is also the possibility that patients may develop viral hepatitis-like manifestations, pupillary constriction, dysregulation, paralytic strabismus, etc. This drug has potential neuromuscular toxicity especially in children and should be avoided for prolonged or excessive use. For malnutrition or anemia the state should be corrected before starting this drug. Patients with hepatic or renal insufficiency, neurological disorders, or epilepsy should be prohibited from using this drug, and should be observed during the course of administration.