Experts say codeine is the most effective. It not only stops coughing but reduces bronchial irritation and relieves pain. But its use is regulated since it is a narcotic and can be abused. To avoid this, follow the prescribed dosage and do not take the drug for more than a week. If coughing persists beyond that, see a doctor. High doses of codeine can cause lightheadedness, sleepiness, nausea, vomiting, loss of appetite or sweating. Over-dosage can lead to coma, slow heartbeat, low blood pressure, convulsions and cardiac arrest.

"Do not take codeine if you know you are allergic or sensitive to it. Use this drug with extreme caution if you suffer from asthma or other breathing problems. Long-term use of this drug may cause dependence or addiction. Codeine is a respiratory depressant and affects the central nervous system, producing sleepiness, tiredness, and/or inability to concentrate. Be careful if you're driving, operating machines, or performing other functions requiring concentration," warned Drs. Gilbert I. Simon and Harold M. Silverman in the "The Pill Book."

Dextromethorphan works the same way as codeine but can be purchased over-the-counter. It is usually given in place of codeine since it is just as effective but believed to be non-narcotic. Ironically, that is not the case since it is the main ingredi¬ent of the most commonly-abused cough syrups.

"Dextromethorphan is a safe and effective active ingredient found in many nonprescription cough syrups, tablets, and gel caps. When used accordingly to medicine label directions, the ingredient dextromethorphan produces few side effects and has a long history of safety. When abused in large amounts, it can produce a 'high' feeling as well as a number of dangerous side effects," according to The Partnership for a Drug-free America.

If coughing is due to allergy, an antihistamine like diphenhydramine may help. This medication blocks the effects of histamine, a chemical released by the body during an allergic reaction. By doing so, the drug treats or prevents the symptoms of allergy and also sup¬presses coughing. Its main side effect, however, is drowsiness which is why this drug is best taken at bedtime.

Other minor side effects of diphenhydramine are blurred vision, confusion, constipation, dizziness, headache, stomach upset and loss of appetite. Tell your doctor if you experience changes in menstruation, clumsiness, difficulty or painful urination, palpitations, ringing in the ears and shortness of breath.

Aside from codeine, dextromethorphan, and diphenhydramine, are there other effective cough suppressants? Find out in the fourth part of this series.

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