**1. Introduction**

Most people are exposed to various diseases with minimal opportunities for conventional means of treatment. The people, therefore, rely on traditional herbal medicine [1]. This has made natural products remain a major source of remedies in traditional medicine [2]. Sick people are, therefore, likely to take herbal medication that is easily available before seeking treatment in the orthodox health sector for the recommended form of treatment. This leads to herbal-drug interactions [3]. This has necessitated studies of various medicinal plants when used in combination, which will act as makers for herbal formulations.

Ginger, *Zingiber officinale* Roscoe, belongs to the genus *Zingiber* Mill. which has 149 plant species under the family Zingiberaceae [3]. The plant species are native to Asia but it is currently cultivated in various parts of the world, especially in the tropics [2]. This is because of its wide dietary use as a spice and has long history of medicinal value [4]. The underground stem (rhizome) is the most widely used

part of ginger. Preference for the rhizome is attributed to the fact that most phytochemicals occur in the rhizome which give the plant its dietary and medicinal benefits [1]. These benefits are enhanced when the plant species being used in combination.

Ginger rhizome has been prescribed for the treatment of various diseases [5] in most traditional and complementary systems of treatment such as homeopathy, Ayurveda, Chinese, Unani Tibb, and Siddha [6]. The plant has been used as an antioxidant [7], antibacterial [8], anticancer [9], anti-inflammation [4], antidepressant [10], regulation of blood sugar level, mensural irregularity [3], treatment of nausea and vomiting, post-operative nausea and vomiting [11], mitigation of rheumatoid arthritis/osteoarthritis/joint and muscle pain, and many other medicinal uses [3]. Studies have been done to determine the activities of ginger when used singly and in combination.

To enhance the medicinal activity of ginger, the rhizome of the plant has been used in combination with other plant extracts, pure compounds, and approved drug in the treatment of various diseases in traditional medicine and in herbal tea formulations, considering tea is the second most widely consumed after water [12]. Phytochemicals present in ginger, especially polyphenols, provide ginger herbal teas with various medicinal properties [13] when combined with phytochemicals from other plants especially polyphenolic compounds [14–16].

The long period and cost incurred in the isolation of pure compounds from plants in drug discovery for conventional medicine buttresses the importance of drug combination studies in phytomedicine [17]. Unlike the use of pharmaceutical drugs whose activity is based on a single active ingredient, in combinations, numerous phytochemicals act collectively [14, 18]. Most of these combinations have shown synergism in prevention and treatment of various diseases and disease conditions. The current chapter, therefore, explored the pharmacological benefits of *Zingiber officinale* when used in combination.
