Albendazole is the first-line drug for treating hookworm infection because it effectively inhibits microtubule synthesis in the parasite, leading to its death. It is highly effective, safe, and has a broad spectrum against soil-transmitted helminths including Ancylostoma duodenale and Necator americanus. Albendazole's single-dose therapy ensures good patient compliance and rapid eradication of the infection. Other options like metronidazole and chloroquine are not effective against hookworms, and praziquantel is used primarily for trematodes and cestodes, not nematodes such as hookworms.

Reference: Harrison’s Principles of Internal Medicine, J. Larry Jameson, Edition 20th.