Pharmacology of Poppy Alkaloids: Minor Opium Alkaloids

The pharmacology and biology of minor opium alkaloids have been surveyed previously in two comprehensive reviews (). Thebaine The pharmacology of thebaine was summarized by Reynolds and Randall in 1957 and studied comprehensively by a WHO Advisory Group in 1980. The pharmacological actions of thebaine in various isolated organs have been studied. Thebaine can induce a temporary decrease in blood pressure in anaesthetized dogs and this depressor effect showed a marked tachyphylaxis. In isolated guinea pig atrium, thebaine decreased the heart rate and contractions depending on the concentration. In isolated rabbit ileum it decreased the peristaltic movement and contractions (). The predominant effect of thebaine is stimulation of the central nervous system. In the mouse, rabbit, cat and dog increases in motor activity and reflex excitability were observed at doses around 2-10mg/kg s.c. or i.m. The Straub-tail response was noted only occasionally. The effects of thebaine on body temperature and respiration have also been studied. Convulsions were observed in almost all species of animals including the frog, pigeon, mouse, guinea pig, cat and dog. Transient tremors, restlessness and convulsions were observed in the Read more […]

The Therapeutic Potential For Cannabis

«Cannabis Use and Abuse by Man: An Historical Perspective» of this site provides a fascinating, historical account of the use of cannabis across many cultures and centuries. Suffice it to say here that any natural substance with over 5000 years of medical history will have attached to it a heritage of hearsay and legend through which one must sift to identify areas of true therapeutic potential for us in the late twentieth century and beyond. A summary of conditions for which cannabis has been used, ranging through various shades of rationality, appears in Table Medicinal and quasi-medicinal uses for cannabis and its derivatives: Indications for which only anecdote or reports of traditional use exist: aphrodisiac muscular spasm in rabies / tetanus Huntingdon’s chorea jaundice toothache earache tumour growth cough hysteria insanity menstrual cramps rheumatism movement disorders gut spasm pyrexia inflammed tonsils migraine headache increasing uterine  contractions in childbirth urinary retention/ bladder spasm parasite infection fatigue allergy fever herpetic pain hypertension joint inflammation diarrhoea malaria forgetfulness Indications Read more […]

Specific Medicinal Uses of Cannabis

The historical and contemporary, medicinal uses of cannabis have been reviewed on several occasions. Perhaps the earliest published report to contain at least some objectivity on the subject was that of O’Shaughnessy (1842), an Irish surgeon, working in India, who described the analgesic, anticonvulsant and muscle relaxant properties of the drug. This report triggered the appearance of over 100 publications on the medicinal use of cannabis in American and European medical journals over the next 60 years. One such use was to treat nausea and vomiting; but it was not until the advent of potent cancer chemotherapeutic drugs that the antiemetic properties of cannabis became more widely investigated and then employed. One can argue that the available clinical evidence of efficacy is stronger here than for any other application and that proponents of its use are most likely to be successful in arguing that cannabis should be re-scheduled (to permit its use as a medicine) because it has a “currently accepted medical use”. Specific Medicinal Uses of Cannabis: Use as an Antiemetic Specific Medicinal Uses of Cannabis: Glaucoma Specific Medicinal Uses of Cannabis: Multiple Sclerosis Spastic Conditions A discussion Read more […]

Specific Medicinal Uses of Cannabis: Glaucoma

Cannabis smoking and the oral ingestion of several of its derivatives have been shown to cause an appreciable drop in intraocular pressure (); and it is known that patients with open angle closure glaucoma smoke cannabis for this purpose. Cannabis When smoked, cannabis containing the equivalent of 20–30 mg of THC has been shown to lower intraocular pressure in an heterogeneous group of glaucoma patients and more specifically, patients with open angle glaucoma. However, the treatment was not without side effects: six of 32 patients developed severe systemic hypotension; this was significantly greater in hypertensive glaucoma patients. Cannabis caused a dose-related, clinically significant, reduction in intraocular pressure of 25– 30%, occurring at 1 hour and lasting 5–6 hours, which was discrete from the sedative effects of the drug. Orthostatic hypotension was observed mainly in cannabis-naive patients. Cannabis does not cure glaucoma but has been shown to slow progressive sight loss when conventional medicines have failed or where the risks of surgery are too great. Tolerance to this effect of cannabis has not been observed; but the degree of reduction in intraocular pressure seen in cannabis-naive patients Read more […]

Coleus spp.

The Genus Coleus More than 300 species belong to the genus Coleus, a member of the family Lamiaceae. Coleus species are native to tropical and subtropical regions of Africa, Australia, the East Indies, the Malay Archipelago, and the Philippines. Some species, especially those with showy colorful foliage, are grown as ornamentals all over the world. In India, tubers of some Coleus species, namely, C. tuberosus and C. forskohlii, are eaten as vegetables and pickles, leaves of other Coleus species (e.g. C. amboinicus) are used as spices. Preparations from several Coleus species are used in Ayurvedic medicine in India, e.g., preparations from C. amboinicus are active against skin problems and worms. Other preparations from Coleus are traditionally used against heart diseases, abdominal colic, respiratory disorders, painful micturition, insomnia, and convulsions. The genus Coleus was first described by de Loureiro in 1790. The name Coleus is derived from the Greek work koleos, which means sheath. This relates to a typical characteristic of Coleus, where the four filaments fuse at the bottom to form a sheath around the style (de Loureiro 1790). Plants of the genus Coleus grow as herbaceous perennials, subshrubs, and low Read more […]


DIURETICS are used to reduce fluid in the body by increasing the excretion of electrolytes by the kidney — so increasing urine production. They have an extensive use. Reducing oedema is, in itself, of benefit in some disorders, and diuretics may be used in acute pulmonary oedema, congestive heart failure, some liver and kidney disease, glaucoma and in certain electrolyte disturbances, such as hypercalcaemia and hyperkalcaemia. The commonest use of diuretics is in antihypertensive therapy, where their action of reducing oedema is of value in reducing the load on the heart, which then — over some days or weeks — gives way to a beneficial reduction in blood pressure (that seems associated with vasodilator action). See ANTIHYPERTENSIVE AGENTS. In relation to their specific actions and uses, diuretics can be divided into a number of distinct classes. Osmotic diuretics (e.g. mannitol, urea) are inert compounds that are secreted into the proximal tubules of the kidney, and are not reabsorbed, so carry salts and water with them into the urine. Loop diuretics (e.g. ethacrynic acid, bumetanide, frusemide) have a vigorous action on the ascending tubules of the loop of Henle (inhibiting resorption of sodium and water, Read more […]

Diseases of the Eye and Ear

  Herbs For Diseases Of The Eye And Ear A number of eye and ear diseases may be treated with herbal therapy. They include cataracts, conjunctivitis, corneal ulcers, glaucoma, keratoconjuntivitis sicca, and otitis (chronic and acute). Many of today’s ophthalmic preparations have origins in ethnobotanical history. Atropine has been derived from solanaceous plants, physostigmine was used as a poison, and pilocarpine was used by Amazonians as a panacea. For chronic or serious eye problems, referral to an ophthalmologist is always recommended. For mild conditions or as adjunctive therapy herbs can be used as eye washes or eye drops. Fresh herbal tea should be made fresh daily and kept refrigerated when not in use. Sterile saline can be used to infuse the herb. Consider the systemic implications or associations of eye conditions and consider herbal treatment for pain relief, immune modulation, vulnery (healing) action, antiinflammatory effects, and health support. Cataracts Corneal Ulcers Strategy Trauma to the cornea must occur for microbial colonization to occur. Consider herpes virus infection in cats with corneal ulcers. Topical Aloe gel (Aloe vera) has been advocated for the treatment of corneal ulcers Read more […]


Strategy Cataracts can be caused by toxic insult (chemotherapy), nutritional deficiencies, heredity, genetic predisposition, or diabetes, as well as endogenous causes such as uveitis, retinal degeneration (PRA), and glaucoma. Referral to a veterinary ophthalmologist and possible surgical treatment is warranted, but if that is not possible then herbal support may be beneficial. Use herbs that are high in antioxidants and that improve circulation. Botanicals such as Bilberry (Vaccinium myrtillus) may be helpful. In diabetic cataracts, flavonoids, particularly Quercetin, are potent inhibitors of aldose reductase. In a study of people with senile cataracts, a combination of Bilberry (standardized to 25% anthocyanosides; given at a dose of 180 mg twice daily) and vitamin E (100 mg twice daily) that was given for 4 months halted progression in 96% of patients compared to 76% of the control group. In a study in rats with early senile cataract and macular degeneration, the effect of Bilberry was investigated over 1.5 to 3 months. The treatment group was given a diet supplemented with 25% Bilberry extract (20 mg / kg, including 4.5 mg of antocianidin) or vitamin E (40 mg / kg). At the end of the study, more than 70% of the Read more […]

Plants Used in African and South American Traditional Medicine

African traditional medicine, which is diverse because of the vast range of habitats, languages and cultural groups, has a long history of use, and in some countries up to 90% of the population relies on plants as the only source of medicines. Countries north of the Sahara have a similar ethnopharmacology because of an influence from Islamic cultures over many centuries. Sub-Saharan cultures are more diverse but do share some common features, such as the consideration of spiritual influences and beings in the disease and healing process. In sub-Saharan Africa, the influence of European culture came quite late and was diversifled because of the different colonial powers and the climate being generally not very amenable to growing some of the traditional European plants. Therefore, the endemic medical systems were arguably more preserved than in many parts of South America, where European domination occurred two or three centuries earlier. However, in the more remote parts of the continent, especially where there was also considerable biodiversity, extensive knowledge about the medicinal uses of the local plants remained, and consequently, several drugs have been included in European medicine over the years. Physostigma Read more […]


ANTISYMPATHETIC AGENTS is a grouping of convenience intended to encompass all agents acting by one of the many mechanisms that lead to a reduction in the actions of the sympathetic nervous system, including those of poorly defined mechanism that are known to have this overall action. Antisympathetics are of particular importance in reducing vasomotor tone, and thence blood pressure. There are many of them and they will be grouped by site and mechanism of action. See also ANTIHYPERTENSIVE AGENTS. Central mechanisms. Some agents may act within the CNS to modify autonomic control of sympathetic tone and blood pressure. Clonidine inhibits release of noradrenaline by an agonist action at the autoinhibitory alpha2-adrenoceptors on sympathetic nerve endings. Methyldopa is thought to work, at least in part, centrally, acting both as an inhibitory false substrate in the biosynthetic pathway, also producing an active metabolite with actions at α2-adrenoceptors. Rauwolfia alkaloids, especially reserpine, which inhibit the monoamine transporters, were at one time used to treat hypertension, but the side-effects are marked. Biosynthetic pathway inhibitors. In both the central and periphery nervous systems, the biosynthetic Read more […]