Ephedrine heart block

Ephedrine, given im/iv/sc, is indicated for the treatment of acute hypotensive states, treatment of Adams-Stokes syndrome with complete heart block, stimulation of the central nervous system (CNS) to combat narcolepsy and depressive states, treatment of acute bronchospasm, treatment of enuresis, and treatment of myasthenia gravis. When given in nasal form, ephedrine is used in the treatment of nasal congestion, promotion of nasal or sinus drainage, or relief of eustachian tube congestion. 

In complete heart block with Stokes-Adams syncope, ephedrine may prove of value in a manner similar to epinephrine. In the attempt to increase ventricular rate and prevent ventricular asystole, an initial dose of about 8 mg of ephedrine sulfate orally may be tried. Later, the dosage may be increased to 25 mg three or four times daily. Syncope due to ventricular tachycardia can also be prevented in some cases with ephedrine. 

P effects, nonselective (i.e. pj + Pj) isoprenaline (isoproterenol). Its uses as bronchodilator (P2), for positive cardiac inotropic effect and to enhance conduction in heart block (p, pp have been largely superseded by agents with a more appropriately selective profile of effects. Other agents with nonselective P effects, ephedrine, orciprenaline, are also obsolete for asthma. 

Physicians routinely used intravenous ephedrine for the prophylaxis and treatment of hypotension caused by spinal anesthesia particularly during caesarean section (9). In the past, ephedrine was used to treat Stokes-Adams attacks (complete heart block), and was also recommended as a treatment for narcolepsy. Over the years, ephedrine has been replaced by other, more effective agents (10), and the advent of highly selective [3-agonists has mostly eliminated the need to use ephedrine in treating asthma. 

In the past, ephedrine was used to treat Stokes-Adams attacks with complete heart block and as a CNS stimulant in narcolepsy and depressive states. It has been replaced by alternate treatments in each of these disorders. In addition, its use as a bronchodilator in patients with asthma has become much less extensive with the development of p2-selective agonists. Ephedrine has been used to promote urinary continence, although its efficacy is not clear. Indeed, the drug may cause urinary retention, particularly in men with benign prostatic hyperplasia. Ephedrine also has been used to treat the hypotension that may occur with spinal anesthesia. 

Ephedrine helps to increase the blood pressure at a therapeutic dose level in two different ways first by enhancing peripheral vasoconstriction. It is found to exert a stimulant action on the respiratory centre. It shows a wide spectrum of actions, namely reduction in the activity of the uterus, bronchodilatation and lowering of intestinal tone and motility. Ephedrine is also used in postural hypotension and in subjects having more or less complete heart block. 

Ephedrine may be used with success in combating the fall of blood pressure in spinal anesthesia, in the treatment of bronchial asthma (bronchodilatation), hay fever, and other allergic conditions. It relieves whooping cough. Ephedrine has been used both for the prevention and the cure of attacks of heart block known as Stokes-Adam s syndrome. Use of ephedrine in the prevention of the pathological sleep of narcolepsy is now replaced by its more efficient chemical relative, deoxynorephedrine (Benzedrine). Ephedrine is of value in the treatment of myasthenia... 

Correct answer = D. Reserpine blocks the uptake of norepinephrine into intracellular storage vesicles, resulting in depletion of norepinephrine and gradual decline in blood pressure. Phenylephrine is a pure vasoconstrictor and raises systolic and diastolic blood pressures. Dopamine raises systolic and diastolic blood pressures by stimulating the heart and (at high doses) causing vasoconstriction. Ephedrine raises systolic and diastolic blood pressures by vasoconstriction and cardiac stimulation. Norepinephrine has a pressor effect. 

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