Medication (noun)

1. A substance used to treat an illness or medical condition.
2. A drug or medicine.
3. The act or process of treating an illness or injury with medicine.
4. The treatment of an illness or injury with medicine.

Origin:

Late middle english: from latin medicatio(n-), from medicare "heal".

Examples:

1. He took medication for his headache.
2. She took medication for her high blood pressure.
3. The medication helped him to feel better.
4. The medication was prescribed by the doctor.
5. The medication had side effects.