An antihistamine is a medicine for an allergy — that unpleasant reaction to pollen, dust, some foods, or a sting. Your body makes a chemical called histamine when it thinks something is a problem, and that is a big reason you sneeze, itch, or swell.

An antihistamine is a medicine for an allergyantihistamine是一種治療過敏的藥 — that unpleasant reaction to pollen, dust, some foods, or a sting也就是身體對花粉、灰塵、某些食物，或叮咬產生的那種不舒服的反應。Your body makes a chemical called histamine when it thinks something is a problem你的身體覺得有東西是問題時，會製造一種叫做histamine（組織胺）的化學物質, and that is a big reason you sneeze, itch, or swell這也是你會打噴嚏、發癢，或腫起來的主要原因。

An antihistamine does not kill the pollen or the food. It blocks histamine, so those feelings calm down. Doctors give it for hay fever, itchy skin, and some insect bites.

An antihistamine does not kill the pollen or the foodantihistamine不會殺死花粉或食物。It blocks histamine它阻斷的是histamine, so those feelings calm down所以那些不舒服的感覺才會緩和下來。Doctors give it for hay fever, itchy skin, and some insect bites醫生會開它來治花粉症、皮膚癢，和一些昆蟲叮咬。

Older kinds can make you sleepy; some people even take those at night on purpose. Newer kinds are made so you can stay awake.

Older kinds can make you sleepy比較舊的種類會讓你想睡; some people even take those at night on purpose有些人甚至故意在晚上服用這種。Newer kinds are made so you can stay awake比較新的種類則是設計成讓你可以保持清醒。

In everyday talk people often say allergy medicine, which is looser — that bag can also hold other drugs. Antihistamine is the more exact word, a bit more doctor-like, but still common on the box.

In everyday talk在日常對話裡, people often say allergy medicine大家常說allergy medicine（過敏藥）, which is looser這個說法範圍比較鬆散 — that bag can also hold other drugs這個說法底下也可能包含其他種藥。Antihistamine is the more exact wordantihistamine是比較精確的字, a bit more doctor-like聽起來比較像醫生會用的詞, but still common on the box不過藥盒上還是很常看到。