- antispasmodic
- azathioprine
- antidiuretic
- aperient
- antidepressant drug
- anthelmintic
- anti_inflammatory
- antipyretic
- antiarrhythmic medication
- anti_inflammatory drug
- allopurinol
- antidepressant
- astringent
- antiarrhythmic
- acyclovir
- angiogenesis inhibitor
- antiarrhythmic drug
- antidiuretic drug
- antispasmodic agent
- antidiarrheal
- atomic cocktail
- Atromid_S
- astringent drug
- amrinone
- antidiarrheal drug
- Antabuse
- antiseptic
- alendronate
- anodyne
- antiprotozoal
- anthelminthic
- APC
- astilbe
- alumroot
- agrimony
- Atropa belladonna
- Aureolaria virginica
- Armoracia rusticana
- American pennyroyal
- American gentian
- alpine coltsfoot
- astrantia
- American licorice
- asparagus fern
- asclepiad
- Apium graveolens
- achillea
- Asparagus plumosus
- Aureolaria pedicularia
- Aspidistra elatio