Toxic Medicines
The Safe use of Potent Medicines
The Safe use of Potent Medicines
Introduction
In all Traditional Medicine systems, there are toxic and potentially Fatal medicines that are used from the Plant, Mineral and Animal Kingdoms. Despite the fact that many of these medicines are prohibited from use in modern western society, they continue to be used in many traditional cultures, especially in the East and Middle East, but also in Africa, South America and elsewhere.
Paracelsus famously said "Only the Dose makes Poison". And this point is most important. Literally anything can be toxic in overdose, even water, the most common substance in our body, and our second most essential input after air.
With this in mind it stands to reason that these medicines are not "Toxic", but "Potent". Potent in that they can potentially be toxic if overdosed or misused.
In all Traditional Medicine systems, there are toxic and potentially Fatal medicines that are used from the Plant, Mineral and Animal Kingdoms. Despite the fact that many of these medicines are prohibited from use in modern western society, they continue to be used in many traditional cultures, especially in the East and Middle East, but also in Africa, South America and elsewhere.
Paracelsus famously said "Only the Dose makes Poison". And this point is most important. Literally anything can be toxic in overdose, even water, the most common substance in our body, and our second most essential input after air.
With this in mind it stands to reason that these medicines are not "Toxic", but "Potent". Potent in that they can potentially be toxic if overdosed or misused.
"Only the Dose makes Poison"
(Paracelsus)
(Paracelsus)
Safety Factor is ascertained by dividing the lethal dose by the therapeutic dose. So for example if 100mg is the therapeutic dose and 1 gram is enough to kill, it has a safety factor of 10. Many medicines and even alcohol have a safety factor as low as 5. Paracetamol; is a good example, 2 pills for a headache, but 10 pills in one sitting can kill you.
So the primary concern is how close the therapeutic dose is to the toxic dose. If an herb is used in doses of 500mg, and 2.5 grams could be fatal, this represents a safety factor equivalent to many common and over-the-counter medicines already in use.
Of course, Safety Factor is not the only concern as far as toxic or potent medicines are concerned. For example, some medicines are accumulative toxins which may have a good Safety Factor in acute usage, but become toxic with continued use as they accumulate in certain organs. The heavy metals are examples of this.
"Even a strong poison can become an
excellent medicine if administered properly,
on the other hand even the most useful
medicine acts as a poison if not handled correctly"
(Charak)
excellent medicine if administered properly,
on the other hand even the most useful
medicine acts as a poison if not handled correctly"
(Charak)
Main Types of Poison
Toxins can be divided into the types of toxic substance. An overview of primary toxic categories of herbal medicines includes:
All of these functions have potential therapeutic effects. For example, Irritant and Caustic medicines may be stimulants in therapeutic doses, Cardiotoxins may be useful Heart medicines in correct dose (Digoxin from Foxglove being an example), some Hemolytic medicines can be effective against Cancer, and some Neurotoxins can be used for Nervous diseases (such as the use of Scorpion and Centipded in TCM).
Of course many Toxin medicines are effective against pathogens such as bacteria or parasites, and some potently increase immune response.
Main types of Poisoning
Poisoning can be divided into Acute and Chronic.
Acute Poisoning is achieved by taking an excessive dose, that is, a dose beyond therapeutic effect. In some cases symptoms develop quickly while in other cases symptoms maybe delayed for days.
Chronic poisoning occurs with repeated exposure over a period of time. Only certain poisons are prone to chronic toxicity as many poisons are broken down or expelled from the body quite rapidly. When the half life of a drug is 24 hours or longer and the patient is taking doses daily, an accumulative effect leading to chronic poisoning is a potential. Of course, this can be averted by having regular pauses in treatment. For example a pause after 2–3 weeks of using herbs that contain pyrrolizidine alkaloids can avert chronic toxicity.
Heavy metals such as Lead and Mercury are apt to cause chronic poisoning with repeated low dose exposure. There is some interesting research to show that Heavy metals processed according to Ayurvedic texts can be given in therapeutic doses without toxic effects or accumulation. The most interesting have been Mercurial medicines and Cinnabar in particular. However, far more research needs to be done before these heavy metals are accepted into modern practice in the West.
Methods of Preparing Toxic Medicines
Three principle ways are used to prepared toxic medicines:
There are various specific and unique ways of preparing the various toxic medicines, but the above three methods cover the large majority. Some toxic medicines have a number of stages that use a combination of the above methods.
Toxic Alkaloids
By far the most common group of phytochemicals that are classed as poisons are the Alkaloids. This potent class of medicines includes compounds such as Morphine, Caffeine, Cocaine and Nicotine. Some of these are also narcotic, some have other potent effects on the CNS, and various other potent effects on the body.
Apart from Narcotic alkaloid-containing plants, the most controversial class of alkaloids in Traditional Medicine are the pyrrolizidine-containing herbs. This is found in a number of important herbal medicines including Comfrey, Coltsfoot, Borage, Cynoglossum spp. etc. However, these alkaloids have been found toxic to the liver, primarily in animal studies. There has been a general ban on herbs containing these alkaloids in many western countries, despite many of these herbs having an long history of apparently safe use.
Some of our most potent medicines are alkaloid-containing, unfortunately, many of these are illegal for use and are therefore obsolete in modern practice..
Aristolchic acid
Another important toxic Phytochemical in traditional medicine is Aristolchic acid, found primarily in Aristolchia (Birthwort) and Asarum species. Aristolchic acid is toxic to the Kidneys and Liver, is mutagenic and carcinogenic. Nevertheless these herbs have been important medicines in Traditional Medicine, and while Aristolchia species are banned for use in many countries they are still used in Unani, TCM, Ayurveda and Tibetan Medicine, although sparingly. Asarum species are still frequently used, particularly in TCM.
It should be pointed out that these herbs are most typically used in formula where they constitute a small proportion, often around 5%. Despite this, the Birthwort species are obsolete in modern western practice.
Toxins can be divided into the types of toxic substance. An overview of primary toxic categories of herbal medicines includes:
- Irritant & Caustic: are usually very hot and pungent. They burn the tongue if tasted, the stronger can burn the flesh if touched
- Hemolytic: destroy the blood cells, larger doses quickly leading to cardiac failure
- Cardiotoxic: toxic to the Heart. They can also lead to cardiac failure
- Neurotoxic: toxic to the brain and nerves. They may cause paralysis leading to death from respiratory paralysis
- Narcotic: most often used to relieve pain and promote sleep can be toxic in overdose
- Heavy Metal: can have various toxic effects on the body and can be accumulative
All of these functions have potential therapeutic effects. For example, Irritant and Caustic medicines may be stimulants in therapeutic doses, Cardiotoxins may be useful Heart medicines in correct dose (Digoxin from Foxglove being an example), some Hemolytic medicines can be effective against Cancer, and some Neurotoxins can be used for Nervous diseases (such as the use of Scorpion and Centipded in TCM).
Of course many Toxin medicines are effective against pathogens such as bacteria or parasites, and some potently increase immune response.
Main types of Poisoning
Poisoning can be divided into Acute and Chronic.
Acute Poisoning is achieved by taking an excessive dose, that is, a dose beyond therapeutic effect. In some cases symptoms develop quickly while in other cases symptoms maybe delayed for days.
Chronic poisoning occurs with repeated exposure over a period of time. Only certain poisons are prone to chronic toxicity as many poisons are broken down or expelled from the body quite rapidly. When the half life of a drug is 24 hours or longer and the patient is taking doses daily, an accumulative effect leading to chronic poisoning is a potential. Of course, this can be averted by having regular pauses in treatment. For example a pause after 2–3 weeks of using herbs that contain pyrrolizidine alkaloids can avert chronic toxicity.
Heavy metals such as Lead and Mercury are apt to cause chronic poisoning with repeated low dose exposure. There is some interesting research to show that Heavy metals processed according to Ayurvedic texts can be given in therapeutic doses without toxic effects or accumulation. The most interesting have been Mercurial medicines and Cinnabar in particular. However, far more research needs to be done before these heavy metals are accepted into modern practice in the West.
Methods of Preparing Toxic Medicines
Three principle ways are used to prepared toxic medicines:
- Washing or Soaking: plant parts, typically root slices can be soaked in water to wash away some of the toxic compounds. In India, toxic medicines are often hung in a bag in a boiling liquid such as milk. This is a combination of heating and washing.
- Heat: Heat is often used to denature toxic elements such as alkaloids. Prolonged boiling in water such as is done with Aconite or scorching in hot sand as is done with Nux Vomica are examples. This process denatures or destroys toxic alkaloids.
- Acid: Acid, most typically Vinegar, is often used in the preparation of toxic medicines. Vinegar can denature certain chemicals
There are various specific and unique ways of preparing the various toxic medicines, but the above three methods cover the large majority. Some toxic medicines have a number of stages that use a combination of the above methods.
Toxic Alkaloids
By far the most common group of phytochemicals that are classed as poisons are the Alkaloids. This potent class of medicines includes compounds such as Morphine, Caffeine, Cocaine and Nicotine. Some of these are also narcotic, some have other potent effects on the CNS, and various other potent effects on the body.
Apart from Narcotic alkaloid-containing plants, the most controversial class of alkaloids in Traditional Medicine are the pyrrolizidine-containing herbs. This is found in a number of important herbal medicines including Comfrey, Coltsfoot, Borage, Cynoglossum spp. etc. However, these alkaloids have been found toxic to the liver, primarily in animal studies. There has been a general ban on herbs containing these alkaloids in many western countries, despite many of these herbs having an long history of apparently safe use.
Some of our most potent medicines are alkaloid-containing, unfortunately, many of these are illegal for use and are therefore obsolete in modern practice..
Aristolchic acid
Another important toxic Phytochemical in traditional medicine is Aristolchic acid, found primarily in Aristolchia (Birthwort) and Asarum species. Aristolchic acid is toxic to the Kidneys and Liver, is mutagenic and carcinogenic. Nevertheless these herbs have been important medicines in Traditional Medicine, and while Aristolchia species are banned for use in many countries they are still used in Unani, TCM, Ayurveda and Tibetan Medicine, although sparingly. Asarum species are still frequently used, particularly in TCM.
It should be pointed out that these herbs are most typically used in formula where they constitute a small proportion, often around 5%. Despite this, the Birthwort species are obsolete in modern western practice.
Principal Toxic Medicines in MedicineTraditions
General Toxic Medicines
Most of these medicines contain Toxic alkaloids.
Some, such as Bitter Almond and Birthwort contain other toxic compounds.
Abrus precatorius, Jequirity
Aconitum carmichaeli, Fu Zi ('Daughter root')
Aconitum carmichaeli, Wu Tuo ('Mother root')
Aconitum folium, Aconite leaf
Aconitum ferox, Bong nga nag po
Aconitum fischeri, Bong nga ser po
Aconitum napellus
Aristolochia, Birthwort
Asarum, Asarabacca, Xi Xin
Brucea, Ya Dan Zi
Colchicum, Hermodactyl
Crocus, Saffron, Xi Hong Hua
Croton, Ba Dou
Cyclamen, Sowbread
Daphne Gnidium
Digitalis, Foxglove
Gelsemium sempervirens, Yellow Jasmine
Gelsemium elegans, Gou Wen
Gloriosa, Glory Lily
Hellebori nigri, Black Hellebore
Periploca, Xiang Jia Pi
Prunus armeniaca amara, Bitter Almond
Ricinus Semen, Castor Seed
Scilla, Squill
Staphysacre, Stavesacre
Taxus, Yew tree
Tripterygium, Lei Gong Teng
Tylophora, Anthrapachaka
Vervatrum, White Hellebore, Li Lu
Wikstroemia, Le Ge Wang
Irritants – Hydragogue
These medicines are all Hydragogue Cathartics.
They all contain irritant gum-resins
Esula, Spurge
Euphorbia dracunculoides, Saptala
Euphorbia helioscopiae, Ze Qi,
Euphorbia kansui, Gan Sui
Euphorbia lathyris, Caper Spurge, Qian Jin Zi
Euphorbia neriifolia, Snuhi
Euphorbia pekinensis, Jing Da Ji
Euphorbia stracheyi, Khron bu
Euphorbia thymifolia, Dudhi
Euphorbium, Official Spurge
Mezereon, Spurge Olive; Laureola, Spurge Laurel
Narcotics
These contain Alkaloids that have a
potent effect on the Nervous system.
Anisodus, Thang phrom nag po
Belladonna, Deadly Nightshade
Conium, Hemlock
Datura, Stramonium
Hyoscyamus, Henbane
Mandragora, Mandrake
Nux Vomica, Ma Qian Zi
Opium
Przewalskia, Thang phrom dkar po
Minerals
Primary Mineral Toxins are those based on Lead,
Mercury and Arsenic. Other heavy metals can also be Toxic.
Mercury
Litharge
Minium
Arsenolite
Orpiment
Realgar
Animal
Cantharides
Toad