By I. Javier. Medical University of South Carolina.
In the tetanus of horses order sinemet 125mg line, it has been frequently used purchase sinemet 110mg on line, hypodermically, by veterinarians throughout America. Smith, of Leesburg, Florida, told me that in the malarial disorders which prevail in his locality he found indications for its use in nearly all acute cases and almost invariably obtained prompt and satisfactory results. He has occasion to prescribe larger quantities of it than of all other fever and sedative remedies combined. Durham, of Atlanta, Georgia, and several other physicians of the South confirmed Dr. All these physicians unite in the opinion that gelsemium quickly brings about that condition in periodical malarial disorders in which the antiperiodic, quinine, can exercise its happiest influence. It restores secretion, softens and slows the pulse, reduces nerve excitation and irritation, causes a mild transpiration from the skin, and assists in cleaning the tongue. All these conditions must be present if quinine be given to marked advantage and with no unpleasant results. These physicians claim further, that given during the time of the administration of quinine, it prevents undue stimulation of a sensitive nervous system, does away entirely in most cases with the tinnitus aurium, and other unpleasant phenomena, and enhances the influence of the quinine in all lines of its action, the desired effect being obtainable by a less quantity of this antiperiodic than would otherwise be required. Ellingwood’s American Materia Medica, Therapeutics and Pharmacognosy - Page 233 I have heard physicians say that they believed there were times or seasons when gelsemium influenced their patients with the same indications much more directly and positively than at other times. Perhaps this is in line with the theory of “epidemic remedial influence” or “epidemic remedial conditions” advanced by Rademacher and referred to by Scudder and other writers. Co-operative Agents: Cimicifuga racemosa is an excellent remedy with which to combine gelsemium where the muscular system is involved. It promotes the action of gelsemium in all heart troubles, and in irritable and inflammatory conditions of the entire urinary tract. Opium intensifies the effects of this agent, but is slower in its action and its effects are not so quickly dissipated. They are not often prescribed together by those who are familiar with the action of gelsemium. Lobelia and this agent will be found to act well together in certain selected cases; in severe convulsive manifestations especially. When morphine is given for relief of pain during powerful spasms, it acts as an antispasmodic. Gelsemium combined with it when indicated will be found to exercise all of its influence and control the pain which would otherwise continue, and thus prevent the antispasmodic effects of the remedy to an extent. Owen of Texas dissolves one grain of morphine in 240 grains of specific gelsemium. He gives this for premature labor pains in doses of from ten to flfteen drops, and in other conditions where both remedies are indicated, he gives from ten to twenty drops, as in severe persistent lumbago, sometimes with immediate results. Other agents which act harmoniously with it to a greater or less extent are passiflora incarnata, the bromides, and chloral hydrate, conium maculatum, physostigma, veratrum, and Jamaica dogwood. Antagonists—This agent is antagonized by alcohol, by strychnine, nux vomica, digitalis, ammonia and, to a certain extent, by caffeine and belladonna. Antidotes—In overdoses, heat applied, with electricity, and alcoholic stimulants, friction, artificial respiration, and hypodermics of atropine or strychnine should be administered. Physiological Action—Tonic in large doses, irritant, causing nausea, vomiting and diarrhea. Therapy—This is a popular stomachic tonic in cases where enfeeblement has occurred as the result of protracted disease. It has long been given in combination with other tonics or in wine, as an agent in the dyspepsia of the aged, or of gouty patients, and in the gastric inefficiency of infants and children, and to a good advantage in catarrhal diarrhoea. As a tonic to the stomach, and the other organs of digestion and appropriation, in those cases where the system is greatly debilitated by protracted disease, it is one of the best remedies, especially by exhausting fevers of malarial origin. It is of much value in malarial conditions generally and has been used to a great extent instead of quinine. When the periodicity has been overcome by quinine this is a rapid restorative to the system. The tincture of gentian is given freely in conjunction with other tonics and with alteratives. It is given with the tincture of iron in the treatment of anemia complicating malarial disease. It is given in conjunction with the iodide of potassium where a tonic and alterative is demanded, and given alternately with hydrocyanic or hydrochloric acid, it is sometimes of great value in the vomiting of pregnancy. It can be depended Ellingwood’s American Materia Medica, Therapeutics and Pharmacognosy - Page 235 upon as a bitter tonic and constant use will establish a confidence in it. It influences the mucous structures, directly improving their tone and function, overcoming relaxation and debility with a marked improvement of the capillary circulation. From long experience, I have learned to esteem geranium more highly than any other vegetable astringent, where a simple tonic astringent action is needed. It is palatable, prompt, efficient, and invariable in its effects, and entirely devoid of unpleasant influences. Specific Symptomatology—Where there are relaxed, atonic or enfeebled mucous membranes, in the absence of inflammatory action; debilitated conditions remaining after inflammation has subsided; excessive discharges of mucus, serum or blood with these conditions, this agent is indicated. Therapy—In sub-acute diarrhoea, geranium exercises an immediate influence, a single full dose producing a marked impression and improving the tone of the entire gastro-intestinal tract from the first. In chronic diarrhea, no matter how stubborn, it may be given with confidence if the specific conditions are present. In doses of ten drops every two hours, diarrheas of the above described character will promptly subside. It is the remedy for the general relaxation of the gastro-intestinal tract in childhood, with protracted diarrhea. In catarrhal gastritis, where there is profuse secretion with a tendency to ulceration, with, perhaps a mild hemorrhage, this agent is Ellingwood’s American Materia Medica, Therapeutics and Pharmacognosy - Page 236 very useful. It has been claimed that incipient gastric cancer has been cured with geranium, and there is no doubt that it takes precedence over many other remedies, when a diagnosis between severe gastric ulcer and incipient cancer cannot be made without exploratory operation. Its range seems much wider than that of a simple astringent, as it controls pain and rapidly improves the general condition. It has an influence over passive hemorrhage unlike that of other agents, but in violent cases of recent origin it is not the best remedy. The author treated a case of haematuria for nearly two years with absolutely no permanent impression upon the condition. Tubercular bacilli were found in abundance in the blood, which was usually arterial in character and steady in quantity.
Some reentrant circuits are present at birth buy sinemet 110mg with visa, notably those causing supraventricular tachycardias (e safe sinemet 110 mg. However, reentrant circuits that cause ventricular tachycar- dias are almost never congenital, but come into existenceascardiac disease develops during life. In the ventricles, reentrant circuits arise in areas in which normal cardiac tissuebecomes interspersedwith patches of ﬁbrous(scar) tissue, thus forming potential anatomic cir- cuits. Thus, ventricular reentrant circuits usually occuronly when ﬁbrosis develops in the ventricles, such as after a myocardial infarc- tion or with cardiomyopathic diseases. Theoretically, if all anatomic and electrophysiologic criteria for reentry are present, any impulse that enters the circuit at the ap- propriate instant in time induces a reentranttachycardia. The time from the end of the refractory period of the shorter-refractory-period pathway to the end of the refractory period of the pathway with a longer refractory time, during which reentry can be induced, is called the tachycardia zone. Treating reentrant arrhythmias ofteninvolves trying to narrow or abolish the tachycardia zone with antiarrhyth- mic drugs (by using a drug that, onehopes, might increase the re- fractory period of the shorter-refractory-periodpathway, or decrease the refractory period of the longer-refractory-periodpathway). Because reentrant arrhythmias can be reproducibly induced (and terminated)byappropriately timed impulses, these arrhythmias are ideal for study in the electrophysiology laboratory. Inmany instances (very commonly with supraventricular arrhythmias, butonly occa- sionally with ventricular arrhythmias), the pathways involvedinthe reentrant circuit can be precisely mapped, the effectofvarious ther- apies can be assessed,and critical portions of the circuit can even be ablated through the electrode catheter. The channelopathies In recent years, some varieties of tachyarrhythmias have been at- tributed to genetic abnormalities in the channels that mediate ionic ﬂuxes across the cardiaccell membrane. Such “channelopathies”— abnormally functioning channels duetoinheritable mutations—can affectany electrically active cell and are not limited to the heart. For Mechanismsofcardiac tachyarrhythmias 17 instance, some varieties of migraine, epilepsy, periodic paralysis, and muscle disorders are apparently duetochannelopathies. While several distinctive cardiac arrhythmias are now thought to be caused by channelopathies, the most clinically relevantand the most commonchannelopathic arrhythmias are those related to triggered activity. Triggered activity Triggered activity is caused by abnormal ﬂuxes of positive ions into cardiaccells. These ionic ﬂuxes producean abnormal “bump” in the actionpotential during late phase 3 or early phase 4 (Figure 1. Inmost if not all cases, afterdepolarizations are thought to be duetoinherited abnormalities in the channels that control the movementofcalcium ionsacross the cell membrane. If the afterdepolarizations are of sufﬁcientam- plitude, they can trigger the rapid sodium channels (which, as noted, are voltage dependent), and thus cause another actionpotential to be generated. Digitalis-toxic arrhythmias, torsades de pointes, and someof the rare ventricular tachycardias that respond to calcium-blocking agents have all been advanced as arrhythmias that are most likely caused by triggered activity. Clinical features of the major tachyarrhythmias Before considering how antiarrhythmic drugs work, it will be help- fultoreview the salient clinical features of the major cardiac tach- yarrhythmias. Automatic supraventricular tachyarrhythmias Automatic supraventricular arrhythmias are seen almost exclusively in acutely ill patients, most of whom have one of the following condi- tions:myocardial ischemia, acute exacerbationsofchronic lung dis- ease, acute alcohol toxicity, or major electrolyte disturbances. Clinically, the heart rate with automatic atrial tachycardias is usu- ally less than200 beats/min. Like all automatic rhythms, the onset and offset are usually relatively gradual; that is, they oftendisplay warm-up, in which the heart rate accelerates over several cardiac cycles. The arrhythmia is usually associatedwith exacerbation of chronic lung disease, especially in patients receiving theophylline. Further, at least three distinctP-wave morphologies are present, which reﬂects the multifocal ori- gin of atrial activity in this arrhythmia. The basic strategy for treating automatic atrial arrhythmias istoag- gressively treat the underlying illness. Reentrant supraventricular tachyarrhythmias Ingeneral, patients have reentrantsupraventricular tachyarrhyth- mias because they are bornwith abnormal electrical pathways that create potential reentrant circuits. Accordingly (in contrast to pa- tients with automatic supraventricular arrhythmias), these patients most often initially experiencesymptoms when they are young and healthy. Most supraventricular tachyarrhythmias seeninotherwise healthy patients are caused by the mechanism of reentry. The ﬁve general categories of reentrantsupraventricular arrhyth- mias are listedinTable 1. Since the beta pathway conducts more rapidly thandoes the alpha pathway, a normal atrial impulse reaches the ventricles via the beta pathway. Most patients with suchbypass tracts do not have overt Wolff-Parkinson–White syndrome, however. Instead, they have concealed bypass tracts, that is, bypass tracts that are incapable of conducting in the antegrade direction (from the atrium to the ventricles), and therefore never display delta waves. Concealed bypass tracts are able to conduct electrical im- pulses only in the retrograde direction (from the ventricles to the atrium). Intra-atrial reentry differs from automatic tachycardiabecause of its sudden onset and termi- nation,and,like all reentrant arrhythmias, it can be induced by pacing. Thus, the bypass tract may be able to conduct the impulse retrogradely back to the atrium. If so, a reentrant impulse may be established, which trav- els antegradely down the normal conducting system and retrogradely up the bypass tract. In atrial ﬂutter, the atrial activity isregular, in excess of 220 beats/min,and usually displays a typical sawtooth pattern (Figure 1. Note the randomly irregular ventricular re- sponse and the absenceofdiscrete P waves. In atrial ﬁbrillation, the atrial activity is continuousand chaotic, and discrete P waves cannot be distinguished (Figure 1. The ventricular response is completely irregular, reﬂecting the chaotic nature of the atrial activity. Triggered supraventricular tachyarrhythmias The only supraventricular tachycardia commonly attributed to trig- gered activity is that seenwith digitalis toxicity. In fact, the presenceofatrial 26 Chapter 1 tachycardia with block should always make one consider the possi- bility of digitalis toxicity. Atrial ﬂutter and atrial ﬁbrillationcanusually be distinguished by simple inspection. Automatic ventricular tachyarrhythmias Abnormal automaticity accounts for a relatively small proportion of ventricular tachyarrhythmias. As is the case with automatic atrial arrhythmias, automatic ventricular arrhythmias are usually associ- atedwith acute medical conditions, suchasmyocardial ischemia, acid–base disturbances, electrolyte abnormalities, and highadren- ergic tone.
With an increase in guanethidine concentration order sinemet 125mg with amex, norepinephrine is replaced and thus the quantity of neurotransmitters capable of being released is reduced cheap sinemet 300mg without prescription. In response to stimulation, the nerve may release guanethidine, which, however, is not an adrenergic receptor stimulant. In addition to this disturbance and the presence of stores of catecholamines in adrenergic nerve endings, guanethidine also acts on the stores of catecholamines in organs such as the heart, spleen, and aorta. Adrenoblocking Drugs Since it does not pass through the blood–brain barrier, it does not act on the central sym- pathetic neurons. Guanethidine is used for severe hypertension, where use of more universally accepted drugs is not successful. It is a very powerful and long-lasting drug, and its effects last for 2–3 days after using it. It is used for treating hypertension in patients who do not respond to thiazide diuretics. It can be used as an adjuvant drug in thiazide treatment for reaching an optimal level of blood pressure. Treating this with hydrogen iodide removes the methyl-protecting group on the phenyl hydroxyl group and the product (12. It competitively inhibits tyrosine hydroxylase action, thus reducing the formation of epinephrine and norepinephrine. It is used for treating patients with pheochromocytoma, in cases where a rise in the level of catecholamines is observed. It is known that the effect of acetylcholine in certain organs can be reproduced by the alka- loid muscarine, and in other organs by the alkaloid nicotine. The division of cholinore- ceptors into so-called mucarinic (M-cholinoreceptors) and nicotinic (N-cholinoreceptors) is based on this observation. Cholinoreceptors in certain locations have different sensitiv- ities to different drugs. There are more than 10 billion neurons that make up the human nervous system, and they interact with one another through neurotransmitters. Acetylcholine, a number of bio- genic amines (norepinephrine, dopamine, serotonin, and in all likelihood, histamine and norepinephrine), certain amino acids and peptides, and adenosine are neurotransmitters in the central nervous system. Acetylcholine is the primary neurotransmitter in the parasympathetic division of the autonomic nervous system, which mainly innervates the gastrointestinal tract, eyes, heart, respiratory tract, and secretory glands. Although its receptors are crucial for maintaining all normal functions of the body, an extremely small number of illnesses can be explained by the dysfunction of cholinergic regions of the peripheral autonomic system. Although acetylcholine itself is a substance without which normal body function would not be possible, two properties make it extremely undesirable for use as medicinal agents. First, its action is very brief because of the rapid breakdown by cholinesterases, and sec- ond—and more importantly—the diversity of action, which makes it practically impossi- ble to make its action specific in accomplishing certain tasks. However, a number of acetylcholine derivatives are more resistant to cholinesterase action and can have more selective action. Thus, cholinomimetics are those drugs that imitate action of endoge- nously released acetylcholine. Cholinergic receptors are coupled to G proteins (intramem- brane transducers that regulate second messengers). Classifications of these drugs are based on the mechanism of their action, which is exhibited either by direct stimulation of 179 180 13. Cholinomimetics cholinergic receptors by choline esters or cholinomimetic alkaloids, or in an indirect man- ner of inhibiting acetylcholinesterases, which are enzymes responsible for the chemical decomposition of acetylcholine. These, in turn, are subdivided into reversible cholinesterase inhibitors and irreversible cholinesterase inhibitors. So, parasympathetic nerves use acetylcholine as a neurotransmitter and cholinomimetic drugs mimic the action of acetylcholine at its receptors. Indirect-acting (cholinesterase inhibitors), which, in turn, can be reversible or irreversible. At the same time they selectively stimulate uri- nary and gastrointestinal tracts, facilitating emptying of neurogenic bladder in patients after surgery or parturition or with spinal cord injury. Nicotinic receptor agonists mimic the effects of acetylcholine at nicotinic receptors on autonomic ganglionic synapses and skeletal neuromuscular junctions. The single case of medical usefulness is their use as a transdermal patch or as chewing gum for cessation of smoking. These drugs are divided into drugs that stimulate muscarinic (M-cholinoreceptors) or nicotinic (N-cholinoreceptors) receptors. Drugs whose efficacy is primarily connected to stimulation of muscarinic receptors, including choline esters, i. Drugs whose action is based on stimulation of nicotinic receptors include the alkaloids nicotine and lobeline. Despite the fact that these drugs are able to directly stimu- late all cholinergic receptors, their therapeutic efficacy is mediated by reaction with mus- carinic receptors (subtypes M1 and M2). The only difference between these drugs is their duration of action, and to some extent selectivity for receptors. For example, 2-chloroethanol is reacted with trimethylamine, and the resulting N,N,N-trimethylethyl-2-ethanolamine hydrochloride (13. A second method consists of reacting trimethylamine with ethylene oxide, giving N,N,N-trimethylethyl-2-ethanolamine hydrox- ide (13. Finally, acetylcholine is also formed by reacting 2-chloroethanol acetate with trimethylamine [1–7]. Because of the presence of a highly polar, charged ammonium group, acetylcholine does not pene- trate lipid membranes. Because of this, when the drug is introduced externally, it remains in the extracellular space and does not pass through the blood–brain barrier. Acetylcholine does not have therapeutic value as a drug for intravenous administration because of its multi-faceted action and rapid inactivation by cholinesterase. Likewise, it is possible for a collaptoid state to develop, and arterial pressure can rapidly fall and the heart can stop. However, it is used in the form of eye drops to cause miosis during cataract sur- gery, which makes it advantageous because it facilitates quick post-operational recovery. Unlike acetylcholine, methacholine is hydrolyzed only by acetylcholinesterase, and the rate of hydrolysis is significantly less than with acetylcholine. Thus, the action of metha- choline is significantly longer lasting than acetylcholine.
Dosage and vaccination schedule – Child over 1 year and adult: 2 doses administered at least 2 weeks apart – Shake the vial discount sinemet 110 mg overnight delivery, squirt the suspension into the mouth (1 order sinemet 110 mg on line. For young children, the contents of the vial can be drawn up in a syringe and squirted into the mouth. Contra-indications, adverse effects, precautions – Do not administer to children less than one year. If the patient vomits the dose of vaccine, wait for 10 minutes, re-administer the same dose and follow with a larger volume of water. Dosage and vaccination schedule – The 1st dose of vaccine should be administered as soon as possible after exposure, even if the patient seeks medical attention long after exposure (rabies incubation period may last several months). The schedule will depend on the patient’s vaccination status prior to exposure and the route of administration used (follow manufacturer’s instructions). Contra-indications, adverse effects, precautions – No contra-indication for post-exposure vaccination (including during pregnancy and breast-feeding). Booster doses are recommended for persons exposed to permanent or frequent contact with the virus. However, at least 12 hours before reconstitution of the vaccine, the diluent must be refrigerated between 2°C and 8°C so that the diluent and lyophilised powder are at the same temperature: a temperature difference during reconstitution may reduce vaccine efficacy. Contra-indications, adverse effects, precautions – No contra-indication (including during pregnancy and breast-feeding). Remarks – Immunocompetent patients are considered as correctly vaccinated against rabies if they present a document confirming pre-exposure vaccination with 3 doses of cell culture rabies vaccine. After delivery, continue vaccination as described in the table above until the required five doses have been administered. Contra-indications, adverse effects, precautions – Do not administer in the event of significant reactions to a previous dose of tetanus vaccine. Do not freeze – 4 tetAnus AntItoxIn (equIne) ⚠⚠ equine tetanus antitoxin should no longer be used, as there is a risk of hypersensitivity and serum sickness. Tetanus antiserum provides temporary passive immunity against tetanus for 2 weeks. Dosage and duration – Prevention of tetanus Tetanus antiserum is administered in the event of tetanus-prone wounds, e. Child and adult: 1500 Iu as a single dose; 3000 Iu if more than 24 hours has elapsed It is administered as soon as possible after injury, along with the tetanus vaccine, in a separate syringe and injection site. In children between 6 and 9 months, vaccination is only recommended in epidemics, as the risk of virus transmission may be very high. Contra-indications, adverse effects, precautions – Do not administer to patients with history of an allergic reaction to a previous injection of yellow fever vaccine, true allergy to egg, immunodeficiency (e. However, given the severity of yellow fever, the vaccine is administered 4 when the risk of contamination is very high (epidemics, unavoidable travel to regions of high endemicity). However, at least 12 hours before reconstitution of the vaccine, the diluent must be refrigerated between 2°C and 8°C so that the diluent and lyophilised powder are at the same temperature: a temperature difference during reconstitution may reduce vaccine efficacy. Drugs for external use, antiseptics and disinfectants Aciclovir, eye ointment Alcohol-based, solution or gel Artesunate rectal Benzoic acid + Salicylic acid, ointment Benzyl benzoate Calamine Chlorhexidine 5% solution Chlorhexidine 7. There must be no residual powder on hands (use powder-free gloves) and hands must be dry. Rub hands for 20-30 seconds, palm to palm, palm over dorsum, between fingers (fingers interlaced), around the thumbs and nails, until hands are completely dry. Contra-indications, adverse effects, precautions – Do not use if: • hands are visibly dirty or soiled with organic matter (wash hands); • there is residual powder on hands (wash hands); • hands are wet (water dilutes alcohol and impedes drying). Remarks – Dose required and duration of handrubbing may vary depending on the product used. Remarks – Buttocks should be held together for at least 1 minute to ensure retention. If capsules are expelled from the rectum within 30 minutes of insertion, re-administer the treatment. When it is absolutely impossible to transfer a patient to a facility where parenteral antimalarial treatment can be administered, artesunate rectal capsules should be administered once daily until the patient is able to take a 3-day course of an artemisinin-based combination. Child > 12 years Child < 2 years Child 2-12 years and adult 1 part of 25% lotion 1 part of 25% lotion Undiluted Preparation + + 25% lotion 3 parts of water 1 part of water 12 hours (6 hours Contact time 24 hours 24 hours in children < 6 months) – Apply the lotion to the whole body, including scalp, postauricular areas, palms and soles. Contra-indications, adverse effects, precautions – Do not apply to broken or infected skin. In the event of secondary bacterial infection, administer an appropriate local (antiseptic) and/or systemic (antibiotic) treatment 24 to 48 hours before applying benzyl benzoate. In case of ingestion: do not induce vomiting, do not perform gastric lavage; administer activated charcoal. Remarks – Close contacts should be treated at the same time regardless of whether they have symptoms or not. The treatment may be repeated if specific scabies lesions (scabious burrows) are still present after 3 weeks. Remarks – Storage: below 25°C – Once diluted, the solution must be used immediately; do not store the diluted solution (risk of contamination). Therapeutic action – Antiseptic Indications – Antisepsis of umbilical cord in maternity units Presentation – 7. Remarks – Storage: below 25°C – Once open, the mouthwash solution keeps for 4 weeks maximum. Clean medical surfaces, beds, surfaces, equipment Corpses, excreta, devices, equipment, ustensils contaminated with boots surfaces and linen in case of cholera blood and other body in case of cholera (after cleaning) (after cleaning) fluids spills (before cleaning) Concentration 0. Precautions – Handle concentrated products with caution (avoid jolts and exposure to high temperatures or flames). Duration – 2 to 4 weeks Contra-indications, adverse effects, precautions – May cause: headache, local skin eruption or pruritus. Dosage and duration – 500 mg vaginal tablet Adult: one vaginal tablet as a single dose, at bedtime – 100 mg vaginal tablet Adult: one vaginal tablet/day for 6 days, at bedtime Contra-indications, adverse effects, precautions – May cause: local irritation; allergic reactions. At least 6 hours must have elapsed since the last administration of dinoprostone before oxytocin can be given. The % w/w is not equal to the % v/v because the mixture of water and alcohol produces a reduction in volume. For example: 40% v/v = 70° proof (British system) = 80° proof (American system) = 40° in French speaking countries. Preparation – Use 70% v/v ethanol, which is more effective than higher concentrations. To obtain 1 litre of 70% v/v ethanol: • take 785 ml of 90% v/v ethanol, or 730 ml of 95% v/v ethanol, or 707 ml of 99% v/v ethanol; • add distilled or filtered water to make up a volume of 1 litre; • leave to cool and top up with water again to bring the volume back to 1 litre (mixing water and ethanol together produces a reaction whereby volume is reduced).