Carminatives (also called aromatic digestive tonics or aromatic bitters) may be used to relieve symptoms of indigestion, particularly when there is excessive gas. It is believed that carminative agents work, at least in part, by relieving spasms in the intestinal tract.⁹

There are numerous carminative herbs, including European angelica root (Angelica archangelica), anise, Basil, cardamom, cinnamon, cloves, coriander, dill, ginger, oregano, rosemary, sage, lavender, and thyme.¹⁰ Many of these are common kitchen herbs and thus are readily available for making tea to calm an upset stomach. Rosemary is sometimes used to treat indigestion in the elderly by European herbal practitioners.¹¹ The German Commission E monograph suggests a daily intake of 4–6 grams of sage leaf.¹² Pennyroyal is no longer recommended for use in people with indigestion, however, due to potential side effects.

A test tube study demonstrated that oil of oregano, and an extract in the oil called carvacrol in particular, inhibited the growth of Candida albicans far more effectively than a commonly employed antifungal agent called calcium magnesium caprylate.¹³ However, clinical studies are needed to confirm these actions in humans.

Herbs that directly attack microbes include the following: chaparral, eucalyptus, garlic, green tea, lemon balm (antiviral), lomatium, myrrh, olive leaf, onion, oregano, pau d’arco (antifungal), rosemary, sage, sandalwood, St. John’s wort, tea tree oil, thyme, and usnea.

Volatile oils from oregano, thyme, peppermint, tea tree, and rosemary have all demonstrated antifungal action in test tube studies.¹⁴ A recent study compared the anti-Candida effect of oregano oil to that of caprylic acid.¹⁵ The results indicated that oregano oil is over 100 times more potent than caprylic acid, against Candida. Since the volatile oils are quickly absorbed and associated with inducing heartburn, they must be taken in coated capsules, so they do not break down in the stomach but instead are delivered to the small and large intestine. This process is known as “enteric coating.” Some doctors recommend using 0.2 to 0.4 ml of enteric-coated peppermint and/or oregano oil supplements three times per day 20 minutes before meals. However, none of these volatile oils has been studied for their anti-Candida effect in humans.

Volatile oils from oregano, thyme, peppermint, tea tree, and rosemary have all demonstrated antifungal action in test tube studies.¹⁶ A recent study compared the anti-Candida effect of oregano oil to that of caprylic acid.¹⁷ The results indicated that oregano oil is over 100 times more potent than caprylic acid, against Candida. Since the volatile oils are quickly absorbed and associated with inducing heartburn, they must be taken in coated capsules, so they do not break down in the stomach but instead are delivered to the small and large intestine. This process is known as “enteric coating.” Some doctors recommend using 0.2 to 0.4 ml of enteric-coated peppermint and/or oregano oil supplements three times per day 20 minutes before meals. However, none of these volatile oils has been studied for their anti-Candida effect in humans.