Final answer:
Heparin injections are frequently recommended to be administered in the abdomen due to the easier injection and absorption of the medication.
Step-by-step explanation:
Heparin injections are commonly administered in the abdomen. The fatty tissue in the abdomen allows for easier injection and absorption of the medication. The thigh is another site that can be used for heparin injections, but it may be more difficult to self-administer in this area.