TREATMENT OF DISEASES CAUSED BY WORMS                37

      judgment if he is to be trusted with the more or less poisonous drugs
      which constitute our present armamentarium of anthelmintics. He
      can be taught, or could be if we had suitable teachers, a sound know-
      ledge of the other factors involved in anthelmintic medication. He
      cannot be taught to be a person of sound judgment, if he is intrinsically
      a person of unsound judgment ; the poor thinker will continue to be
      a dangerous performer with potent drugs, and will continue to dis-
      credit excellent drugs by obtaining bad results as a result of bad
      judgment.

(2)  The patient must always be considered as to status praesens in connection
      with the other factors, and especially in regard to conditions constitut-
      ing contraindications for treatment. Failure to consider contraindica-
      tions is altogether too common, and is a prolific source of fatalities.

(3)  The parasite must be known definitely and its habits, location, and life
      history taken into consideration. A knowledge of these facts leads to
      sound procedures, and affords an intelligent explanation for certain
      failures.

(4) The parasiticide (the anthelmintic) must be selected not only with reference
      to its known action on the worms to be removed, but also with
      reference to its effects on the patient. These drugs are potent and
      poisonous, they exert a certain amount of unfavourable effect on the
      patient and the practitioner must select his drug and his dosage with
      reference to both of these things.

(5)  The purgative is usually the most important factor in connection with the
      procedure of safety: It must be selected with reference to its known
      action in connection with any anthelmintic, since some purgatives are
      unsuitable with certain anthelmintics, and either afford inadequate
      protection to the patient or diminish the efficacy of the anthelmintic.
      Purgatives should be given in adequate amounts, as small amounts
      are as bad as, or worse than, none. The time and mode of adminis-
      tering the purgative are also important.

(6)  Prophylaxis rounds out the job of treatment. The practitioner has not
      fulfilled his duty to his client until he has not only aided him in his
      trouble, but also told him why he was in trouble, and how to avoid
      similar trouble in the future if the state of our knowledge affords such
      information. The veterinarian who treats a herd of swine in a hot
      lot, and leaves the swine to pick up millions of ascarid eggs from the
      ascarids removed and left there, has an inadequate idea as to his duty
      to his client.