Question: What happens if you inhale helium?
Answer:
If you inhale helium from a balloon, you get a squeaky voice. You may also get light-headed because you're breathing in pure helium gas rather than oxygen-containing air. This can lead to hypoxia or low oxygen. If you take more than a couple of breaths of helium gas, you could pass out. Unless you hit your head when you fall, you're unlikely to suffer any lasting harm from the episode. You may get a headache and a dry nasal passage. Helium is non-toxic and you'll start breathing normal air as soon as you move away from the balloon.