View photos of the medicinal cactus, Selenicereus grandiflorus (Night blooming cereus), profiled in Medicinal Plants of the American Southwest.

A passage from Medicinal Plants of the American Southwest:

Use Night blooming cereus to slow and strengthen a rapid, thready, and excitable pulse. Individuals who tend to be of a nervous temperament and who are prone to palpitations, shortness of breath, and weakness, all resulting from over work or emotional upset will benefit from Night blooming cereus. Similar to Hawthorn, a gloomy and dark outlook accompanying the above symptom set also indicates Night blooming cereus. Older individuals should use it as a heart tonic for mild to moderate heart enlargement or weakness from tobacco use.