proposed amendment to the food and drug regulations project no. 1658 schedule f this notification announces the availability of a letter that provides an opportunity to comment on the proposed addition of six medicinal ingredients to part i of schedule f to the food and drug regulations. description of the medicinal ingredients 1. alitretinoin its salts and derivatives is a retinoid drug that is related to vitamin a. alitretinoin its salts and derivatives are used to treat severe chronic eczema of the hand that has not responded to topical treatment with corticosteroids. because alitretinoin its salts and derivatives can cause severe birth defects its use requires specific and effective pregnancy prevention measures for women of childbearing potential. individualized instructions direct supervision by a practitioner and routine laboratory monitoring are required during treatment. 2. aripiprazole and its salts belong to a grou of medicines called atypical antipsychotic drugs. aripiprazole and its salts are used to treat schizophrenia and bipolar disorder. aripiprazole and its salts should be prescribed by a practitioner who is experienced in the diagnosis of psychiatric disorders. due to the potential for undesirable or severe side effects from aripiprazole and its salts at normal therapeutic dosage levels individualized instructions direct supervision by a practitioner and routine laboratory monitoring are required during treatment. 3. besifloxacin and its salts is an antibiotic used for the treatment of inflammation of the eye caused by bacteria. the use of besifloxacin and its salts requires direct supervision by a practitioner as there may be undesirable or severe side effects at normal therapeutic dosage levels. 4. doripenem its salts and derivatives is a broad-spectrum antibiotic used for the treatment of pneumonia that occurs in a hospital or similar setting. individualized instructions direct practitioner supervision and routine laboratory monitoring are required. doripenem its salts and derivatives may have undesirable or severe side effects at normal therapeutic dosage. 5. saxagliptin and its salts are used to improve blood sugar levels in adult patients with type 2 diabetes. saxagliptin and its salts are used in combination with other drugs used to treat diabetes when diet and exercise and other drugs have failed to adequately control blood sugar levels. saxagliptin and its salts should be used under the supervision of a physician as it is indicated for use in combination with other prescribed drugs and requires routine laboratory monitoring. saxagliptin and its salts may also have undesirable or severe side effects at normal therapeutic dosage levels. 6. sevoflurane is a halogenated inhalation anesthetic that is used for general anesthesia during surgery. individualized instructions direct practitioner supervision and routine laboratory monitoring are required. there is a narrow margin of safety between the therapeutic and toxic dosages. the degree of regulatory control afforded by schedule f prescription drug status coincides with the risk factors associated with each medicinal ingredient. oversight by a practitioner is necessary to ensure that appropriate risk benefit information is considered before the drug containing the medicinal ingredient is administered and that the drug therapy is properly monitored. schedule f is a list of medicinal ingredients the sale of which is controlled under sections c.01.041 to c.01.049 of the food and drug regulations. part i of schedule f lists medicinal ingredients that require a prescription for human use and for veterinary use. part ii of schedule f lists medicinal ingredients that require a prescription for human use but do not require a prescription for veterinary use if so labelled or if in a form unsuitable for human use.