Final answer:
Nitroglycerin is not given by the rectal suppository route but can be administered through other routes such as intravenous drip, oral dosage forms, topical ointment, and sublingual tablets.
Step-by-step explanation:
Nitroglycerin, a medical drug used to relieve chest pain in heart disease, is not given by the rectal suppository route. It can be administered through various routes, such as continuous intravenous drip, oral dosage forms, topical ointment, and sublingual tablets. Rectal suppository is not a commonly used route of administration for nitroglycerin.