Ephedra horsetail – Ephedra equisetina Brg.
A large shrub 1,5 m, families эfedrovыh (Ephedraceae). Grows in Central Asia and Eastern Tien Shan. For medical purposes, harvest the aboveground part of the plant, from which it is made ephedrine.
The chemical composition of ephedra
All organs of the plant and especially in the aerial part contains alkaloids (1 -ephedrine, 1-Pseudoephedrine) , tannins (in particular, tannin).
The pharmacological properties of ephedra
The pharmacological properties of ephedra horsetail determined by the presence of ephedrine in the plant, which chemical structure resembles the action of adrenaline on the body.
Ephedrine belongs to the indirect action adrenomimetikami (sympathomimetic). Mode of action due to its stimulating effect on α- и b-адренорецепторы. It causes peripheral vasoconstriction, in particular vascular mucosal, It has a stimulating effect on the activity of the heart, increases in blood pressure, inhibits peristalsis, dilates the pupil (without affecting the accommodation and intraocular pressure) and bronchi. Besides, Ephedrine stimulates the central nervous system, excites the respiratory center.
By pharmacological properties markedly different from ephedrine epinephrine first and gradually developing a more lasting effect. The smaller intensity of the pharmacological action due to the absence in its chemical structure hydroxyls on the benzene ring. A more lasting impact on the basic system of the body, sometimes measured in hours, It is directly dependent on the presence in the molecule of a long chain. The essential difference from other agonists of ephedrine and adrenaline is its effectiveness when administered and resistance to monoamine oxidase.
The use of ephedra in medicine
Ephedrine hydrochloride is used in asthma, hay fever, krapivnice, serum sickness and other allergic diseases. Besides, a drug used to narrowing of blood vessels and reduce inflammation in rhinitis, and as a means to increase blood pressure during surgery (especially when spinal anesthesia), injuries, infectious diseases, myasthenia, Narcolepsy, poison pills and narcotic drugs, to improve pupil with diagnostic purpose in ophthalmic practice.
In the treatment of patients with bronchial asthma ephedrine since its introduction into medical practice and to date holds a leading position as one of the most effective bronchodilators. Ephedrine is used for the relief of asthma attacks, especially fast-acting injection 5 % solution. Ephedrine provides a longer therapeutic effect, than adrenaline, it is better tolerated by patients.
Ephedrine, adopted in the midst of an asthmatic attack of moderate severity, 20-30 minutes relieves him; passed in a sufficient dose for the night, it prevents the development of a night attack. The degree of sensitivity to ephedrine patients varies widely, threshold doses vary.
Ephedrine dosage must be strictly individualized. It is advisable to combine ephedrine with Dimedrolum. Alternating daily intake of ephedrine with an evening reception dimedrol provides therapeutic results in patients with increased bronchial tone muscles. This does not develop tolerance to ephedrine.
In ophthalmic practice ephedrine used for mydriasis. Instilling 5 % ephedrine hydrochloride solution 2- 3 times during 5 m is 7-10 minutes mydriasis. Advanced ephedrine pupil narrows from the effects of bright light, but slightly, allowing you to explore the fundus. Ephedrine has some advantages compared with atropine: it causes short-term mydriasis, which can be easily removed pilocarpine, and intraocular pressure increases.
Side effects. Nausea, vomiting, slight tremor, dizziness, heartbeat, precordial pain, arterial hypertension, the fear of death, jitters, insomnia, headache, urinary retention, hyperhidrosis, skin rash.
Contraindications: hypertonic disease, atherosclerosis, organic changes in the myocardium (infarct, kardioskleroz), hyperthyroidism, diabetes. Precautions should be prescribed to the elderly and patients with hypersensitivity to sympathomimetic substances.
Dosage forms of ephedra, Dosing and Administration
Available ephedrine hydrochloride (Ephedrine hydrochloride) in powders and tablets, as 5 % solution for 1 mL ampoules, as well as tablets consisting teofedrina, Higher doses inside and under the skin: single 0,05 g, daily 0,15 g.
When taken orally, onset of action observed after 40-60 minutes, a maximum effect occurs after 3-H,5 no, duration of ephedrine hydrochloride is individual and varies from 6 to 8.12 pm.
Dose эfedrina, relieves bronchospasm, depends on the individual patient's sensitivity to the drug, ranging from 12,5 to 50 mg (1,5-2 Tablets). The drug is indicated for non-severe bronchial asthma and chronic obstructive bronchitis in freestyle, emphysema, pneumosclerosis. Inside designate, usually, by 0,025 g 2-3 times a day before meals, single dose can be increased to 2-3 tablets under control pneumotachometry, pulse and blood pressure.
The aerosols 0.5-1 ml 5 % ephedrine solution in dilution 1:3, 1:5 with isotonic sodium chloride solution. The therapeutic effect occurs within 10-15 minutes.
For acute asthma ephedrine drive under the skin at a dose of 0.5-1 ml. During treatment antispastic effect of ephedrine may be reduced, but it recovered after several days of interruption in reception. To avoid insomnia containing ephedrine and its products should not be administered at bedtime.
In patients with chronic pulmonary heart ephedrine often used as part of the tablets teofedrina (theophylline, theobromine, caffeine 0,05 g; amidopirin, phenacetin by 0,2 g, ephedrine hydrochloride, phenobarbital in 0,02 g; extract of belladonna 0,004 g, cytisine 0,0001 g). This combination of drugs is justified not only by the diversity of spectrum, but also mutually influence potentiator. The drug usually start with half tablet. The beaten in the morning is best to take the tablet was still in bed. After 30-40 minutes at an altitude of bronchodilator action the patient can get up and spend a toilet bronchi (expectorate).
Storage – Tablets and capsules are stored in a dark place.
