Which of the following antibiotics is contraindicated for patients allergic to penicillin?

Amoxicillin is a penicillin derivative and is structurally similar to penicillin itself. For patients who have a known allergy to penicillin, taking amoxicillin can lead to an allergic reaction, which may vary from mild to severe, including anaphylaxis. Allergic reactions to penicillin can manifest in various ways, such as rashes, swelling, or respiratory distress, making it crucial for healthcare providers to avoid prescribing amoxicillin to those with this allergy.

In contrast, clindamycin, tetracycline, and ciprofloxacin are not related to penicillin and generally do not pose a risk for individuals with penicillin allergies. Clindamycin is part of the lincosamide class, tetracycline is a separate class of antibiotics, and ciprofloxacin belongs to the fluoroquinolone class. Therefore, these alternatives can be prescribed safely to patients who are allergic to penicillin, making them suitable options in such cases.