What is the danger of hydrochloric acid?

Answer 1

Answer:It's extremely acidic (meaning very low pH) and corrosive. It'll kill you.

Another answer:

Hydrochloric acid will typically not kill you. It is indeed very acidic, but most of the more acute health effects due to intense exposure are reversible. Inhalation of the acid or containing substances will cause coughing, hoarseness, inflammation, and ulceration of the respiratory tract. Severe burns, ulceration, and scarring come from contact with the skin.

Vomiting, diarrhea, and nausea can accompany or follow exposure. Long exposures at a lower dosage (such as occupational) cause problems such as gastritis, chronic bronchitis, and dermatitis. Some erosion and discoloration of the teeth is also possible.

As with any acid, intentional misuse (Drinking it, per say) can indeed be fatal, but you can kill yourself by drinking enough water, so that point is approaching moot.