1. Dactylorhiza maculata
2. Dalibarda repens
3. Danae racemosa
4. Daphne cneorum
5. Daphne gnidium
6. Daphne laureola
7. Daphne mezereum
8. Daphne pontica
9. Dasiphora fruticosa
10. Dasypyrum villosum
11. Date palm
12. Date-plum
13. Datura metel
14. Datura stramonium
15. Daucus carota
16. Decodon verticillatus
17. Delphinium elatum
18. Delphinium grandiflorum
19. Delphinium staphisagria
20. Dendrobium moniliforme
21. Descurainia sophia
22. Desmodium canadense
23. Dianthus alpinus
24. Dianthus armeria
25. Dianthus barbatus
26. Dianthus carthusianorum
27. Dianthus caryophyllus
28. Dianthus chinensis
29. Dianthus deltoides
30. Diapensia lapponica
31. Dicentra cucullaria
32. Dictamnus albus
33. Digitalis ferruginea
34. Digitalis lutea
35. Digitalis purpurea
36. Digitalis thapsi
37. Dill
38. Dillenia indica
39. Dimorphotheca pluvialis
40. Dioscorea alata
41. Dioscorea bulbifera
42. Dioscorea communis
43. Dioscorea oppositifolia
44. Dioscorea pentaphylla
45. Dioscorea villosa
46. Diospyros lotus
47. Diospyros virginiana
48. Diphasiastrum alpinum
49. Diphasiastrum complanatum
50. Diplotaxis muralis
51. Dipsacus fullonum
52. Dipsacus laciniatus
53. Dipsacus pilosus
54. Dirca palustris
55. Distichlis spicata
56. Dittrichia viscosa
57. Dodecatheon meadia
58. Doronicum plantagineum
59. Dorstenia contrajerva
60. Draba verna
61. Dracocephalum moldavica
62. Dragon's mouth
63. Drimia maritima
64. Drosera capensis
65. Drosera indica
66. Drosera rotundifolia
67. Drosophyllum lusitanicum
68. Dryas octopetala
69. Dryopteris cristata
70. Dryopteris filix-mas
71. Dryopteris marginalis
72. Drypis spinosa
73. Dulichium arundinaceum
74. Duranta erecta
75. Dysphania ambrosioides
76. Dysphania botrys
77. Dysphania multifida

Digitalis purpurea

• Foxglove  (Digitalis spp.)

• Usage: Used for heart problems. Is effective, but:

• Whether or not a given quantity of digitalis contains enough digoxin to lead to an overdose depends on the individual plant(s) it's from (each individual plant (even in the same species) has a different digoxin content) so those using digitalis are effectively playing Russian roulette. There is no way of knowing if one pill is good, or if it will lead to an overdose and kill you. As Encyclopedia.com puts it:

Foxglove is no longer used as a heart medicine because the therapeutic dose and the lethal dose are very close. Seasonal variations in the level of cardiac glycosides in the plant make the safe dose impossible to estimate except by an experienced physician and prescriber of the herb who monitors the patient on an hourly basis for signs of overdose. Few living doctors and herbalists can safely use digitalis as a plant extract. Specific standardized doses of pharmaceutical digoxin are used instead.<wiki/List_of_medicinal_plants#cite_note-98">

• The solution is to use pure digoxin, if prescribed by a doctor, because the doses are exactly measured.

• Harmful effects: Side effects may include irregular heart function and death.<wiki/List_of_medicinal_plants#cite_note-Digitalis-99"> Symptoms of digitalis overdose may include "stomach upset, small eye pupils, blurred vision, strong slow pulse, nausea, vomiting, dizziness, excessive urination, fatigue, muscle weakness and tremors, stupor, confusion, convulsions, abnormal heartbeats, and death. Long-term use of digitalis can lead to symptoms of toxicity, including visual halos, yellow-green vision, and stomach upset."<wiki/List_of_medicinal_plants#cite_note-Digitalis-99"> "Even touching the plant with bare skin has been known to cause rashes, headache, and nausea."<wiki/List_of_medicinal_plants#cite_note-theherbbook-7">

Datura stramonium

• Jimson weed  (Datura stramonium)

• Used for: spasmodic coughing, chronic laryngitis, asthma; used as an aphrodisiac in South America<wiki/List_of_medicinal_plants#cite_note-theherbbook-7">
• Insufficient evidence to evaluate efficacy.<wiki/List_of_medicinal_plants#cite_note-jim-137"> Jimson weed leaves are smoked for asthma.<wiki/List_of_medicinal_plants#cite_note-138">
• Harmful effects: Jimson weed is poisonous and can cause dry mouth and extreme thirst, vision problems, nausea and vomiting, fast heart rate, hallucinations, high temperature, seizures, confusion, loss of consciousness, breathing problems, and death.<wiki/List_of_medicinal_plants#cite_note-jim-137"> "The deadly dose for adults is - grams of leaf or - grams of the seeds."<wiki/List_of_medicinal_plants#cite_note-jim-137">

Drimia maritima

• Squill  (Drimia maritima)

• Not enough research to evaluate efficacy for anything.<wiki/List_of_medicinal_plants#cite_note-squill-202"> Used for heart problems, bronchitis, asthma, whooping cough, and wounds.
• Harmful effects: The herb is cardiotoxic and can be lethal, with side effects including stomach irritation, loss of appetite, diarrhea, vomiting, headache, vision changes, depression, confusion, hallucinations, irregular heartbeat, skin rash, miscarriages, seizures, life-threatening abnormal heart rhythms, and death.<wiki/List_of_medicinal_plants#cite_note-squill-202">

Dionaea muscipula

• Venus fly-trap  (Dionaea muscipula)

• Active ingredient plumbagin, claimed to boost the immune system
• Harmful effects: Possible side effects of plumbagin are diarrhea, skin rash, liver damage, and abnormal blood counts.<wiki/List_of_medicinal_plants#cite_note-211"> Plumbagin is mutagenic to Escherichia coli.<wiki/List_of_medicinal_plants#cite_note-212">