If you have the cash for the galaxy hammer, there's a cool area-of-effect move you can do by right-clicking and then mashing left click and c. Basically you get the right-click special attack several times. Even if you can't mash fast enough to kill the enemies before they get knocked back, the knockback effect buys you time to eat food.
I've found that with the acrobat perk + artful enchant you can spam this fast enough that you don't need the regular attack at all. If not, you can forge an emerald or two with the hammer to speed up the regular attack.
Speaking of eating food, with the +2 speed buff from a spicy eel plus coffee, you can run fast enough to just dodge those serpents. I prioritize speed above all else in SC, because fighting enemies takes time that you could be spending getting further down in the mines. You can trade rubies and diamonds to the desert trader for spicy eel and coffee.
@Cptldsilver is absolutely right about eating when you get below half health. To do that faster, you can pause and use the hotkeys to switch to the inventory slot with your food in it. Just pause, switch to food, unpause and immediately eat. If you get used to that you can almost always eat before enemies hit you - I mostly die in Skull Caverns when I'm not paying enough attention to my health bar (which happens embarrassingly often).
