Final answer:
The most common side effect of Accutane is photosensitivity, while the most common side effect of Tetracycline is nausea.
Step-by-step explanation:
The most common side effect of Accutane (isotretinoin) is **photosensitivity**, which refers to an increased sensitivity of the skin to sunlight. This can cause the skin to become easily sunburned.
On the other hand, the most common side effect of Tetracycline is which is a feeling of sickness or discomfort in the stomach.
It's important to note that both medications can have additional side effects, but these are the most frequently reported ones.