1. Iberis gibraltarica
2. Iberis sempervirens
3. Iberis umbellata
4. Ichnocarpus frutescens
5. Ilex aquifolium
6. Ilex cassine
7. Illecebrum verticillatum
8. Impatiens balsamina
9. Impatiens noli-tangere
10. Indigofera tinctoria
11. Inula britannica
12. Inula crithmoides
13. Inula helenium
14. Inula hirta
15. Inula salicina
16. Ionactis linariifolia
17. Ipomoea alba
18. Ipomoea coccinea
19. Ipomoea lacunosa
20. Ipomoea quamoclit
21. Ipomoea triloba
22. Ipomoea violacea
23. Iris foetidissima
24. Iris germanica
25. Iris graminea
26. Iris persica
27. Iris pseudacorus
28. Iris pumila
29. Iris sibirica
30. Iris spuria
31. Iris variegata
32. Iris verna
33. Iris versicolor
34. Iris virginica
35. Iris xiphium
36. Isatis tinctoria
37. Isolepis fluitans
38. Isolepis setacea
39. Itea virginica
40. Iva annua
41. Iva frutescens
42. Ixora coccinea

Isatis tinctoria

• Woad  (Isatis tinctoria)

• In addition to producing a blue dye, woad has alleged medicinal uses. Chemicals from woad might be used to prevent cancer, as woad can produce high levels of glucobrassicin.<wiki/List_of_medicinal_plants#cite_note-219"> Young leaves when damaged can produce more glucobrassicin, up to           times as much.<wiki/List_of_medicinal_plants#cite_note-220">
• Indigo woad Root is a traditional Chinese medicine herb that comes from the roots of woad, but often incorrectly listed under the synonymic name, Isatis indigotica. It is also known as Radix isatidis. The herb is cultivated in various regions of northern China. The roots are harvested during the autumn and dried. The dried root is then processed into granules, which are most commonly consumed dissolved in hot water or tea. The product, called banlangen keli (复方板蓝根颗粒), is very popular throughout China, and used to remove "toxic heat", soothe sore throat and to treat influenza, measles, mumps, syphilis, or scarlet fever. It is also used for pharyngitis, laryngitis, erysipelas, and carbuncle, and to prevent hepatitis A, epidemic meningitis, cancer and inflammation.<wiki/Help:References" title="Help:References">
• Harmful effects: Possible minor side effects include allergic reactions and dizziness; only large dosages or long term usage can be toxic to the kidneys.

Ilex paraguariensis

• Maté  (Ilex paraguariensis)

• Also called: yerba maté
• Consumed as a beverage. It is extremely popular in South America.
• Harmful effects: Non-caffeine-related side effects include an increased risk of mouth, esophageal, laryngeal, kidney, bladder, and lung cancer.<wiki/List_of_medicinal_plants#cite_note-mate-155"><wiki/List_of_medicinal_plants#cite_note-nyu-mate-156">The oral cancer associations may be due to the very high temperatures at which maté tea is traditionally drunk, but the associations with kidney, bladder, and lung cancer would not be temperature related.<wiki/List_of_medicinal_plants#cite_note-nyu-mate-156"> Caffeine-related side effects include insomnia, nervousness and restlessness, stomach upset, nausea and vomiting, increased heart rate and breathing, high blood pressure, headache, ringing in the ears, irregular heartbeats, slowed blood clotting, and worsened diarrhea.<wiki/List_of_medicinal_plants#cite_note-mate-155">
• Best remove it from your diet.

• Impila (Callilepsis laureola)

• A traditional Zulu remedy used for tapeworm, snakebites, infertility, whooping cough, and to kill maggots in cattle. It is also used as a disinfectant.<wiki/List_of_medicinal_plants#cite_note-135">
• It can cause fatal kidney and/or liver failure.<wiki/List_of_medicinal_plants#cite_note-136">