Reflex expectorant

A gastropulmonary reflex Irritation of the upper gastrointestinal tract produces emesis afferent impulses go to the emetic centre in visceral sensible nerves in the gastric mucosa. Emesis starts with saliva secretion and indisposition. The dose of the reflex expectorants is so chosen so that the first stage is reached secretion of less viscous fluid in the bronchial cells. 

Primulae radix is a typical reflex-expectorant the effect is a weak emetic effect, i.e. 

Expectorants enhance the production of respiratory tract fluid and thus faciUtate the mobilisation and discharge of bronchial secretions. Historically, expectorants have been divided iato two classes based on specific mechanisms of action. Stimulant expectorants iacrease respiratory tract secretion by a direct effect on the bronchial secretory cells. Sedative expectorants act by gastric reflex stimulation. Many compounds classed as expectorants have been iaadequately studied and the mechanisms of action are not known with certainty. 

A gastric tube is inserted orally, or nasal intubation may be used if the patient has a hyperactive gag reflex. X-ray or fluoroscopic confirmation that the tip of the radio-opaque tube is in the lowest portion of the stomach is necessary. Ten or 15 minutes after the patient has become calm and adjusted to the presence of the tube, the patient is positioned with the trunlc upright and inclined sfightly to the left. Gastric juice is then aspirated and discarded. After checking that no further juice can be aspirated, note the time and collect and transfer to plastic bottles aU gastric juice that can be aspirated over the next 60 minutes. The patient must be asked to expectorate aH saliva during the collection period. The total volume of the collected juice is recorded and free acid determined by titration as described below. 

The biological availabihty is 35—40%. The effect diminishes by 35% per day. The elimination is not inflnenced by a decreased renal function. Sqnill is often nsed as an expectorant because of its abihty to cause gastric irritation leading to a reflex secretion ftom the bronchioles. 

The ipecacuanha root has three actions expectorant, emetic and amoebicidal. The expectorant action is due to the irritant effect of emetine and cephaeline on the gastrointestinal tract, which causes a reflex increase in the secretion of respiratory tract fluid. The dose is... 

In cases where airways are blocked by secretions, these secretions should be removed. Initial attempts may be made to administer an expectorant agent to promote the expulsion of secretions via the cough reflex. If this is ineffective, postural (head-down) drainage or direct secretion removal by bronchoscope or a nasotracheal cannula should be attempted in the hospital. 

Almost colorless to slightly yellow liquid with an aromatic, pungent odor and the taste of ammonia, d 0.90. Forms an opalescent mixture with water miscible with alcohol. therap CAT Reflex respiratory stimulant. therap cat (vei) By inhalation respiratory and circulatory stimulant. Internally expectorant, diaphoretic, antacid, carminative. Externally counterirritant, and in dilut -ed form to relieve the irritation of insect stings and bites. 

Aminophylline is frequently used for the treatment and control of congestive heart failure, bronchial asthma, Cheyne-Stokes respiration, cardiac paroxysmal dyspnea. It is also a vital component in many cough mixtures so as to reduce the cough reflexes and to cause expectoration. 

Iodides and Other Inoi anic Compounds. Inorganic compounds such as potassium iodide [7681-11 -0]y hydriodic acid [10034-85-2]y antimony potassium tartrate [28300-74-5]y and ammonium chloride [12125-02-9] are thought to act by gastric reflex stimulation. Of these, only the iodides have been studied to any appreciable extent (13). A number of toxic reactions have been associated with both antimony potassium tartrate (14) and inorganic iodides (15,16). Reaction of iodine with glycerol [56-81-5] (qv) produces a stable oiganic iodide mixture, iodinated glycerol [5634-39-9] (14), which has expectorant properties. Formulations of (14) contain no free or ionic iodine, but iodine is released metaboHcally. 

When home remedies don t work, patients often use over-the-counter dmgs or prescription dmgs. The most commonly used are antihistamines (blocks histamines produced by the body), decongestants (reduces swollen nasal mucous membranes), antitussives (suppress the coughing reflex), and expectorants (loosens mucus). 

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