in mice , apomorphine ( 10 mg/kg s.c. ) does not induce a compulsion to gnaw , but pretreatment with antihistamines , viz . pheniramine , chlorpheniramine and mepyramine , in doses ranging from 30 to 60 mg/kg i.p . caused gnawing activity .
C0031408
pheniramine
C0008281
chlorpheniramine