As a pharmacist, I am asked so many questions daily about which cough medicine to choose. I figured this would be great information to pass on to you just in case you have trouble deciding on a cough medication and a doctor or pharmacist is not around.
There are two types of coughs, a productive cough and a non-productive or dry cough. A productive cough produces mucus and is usually very heavy in the chest area often resulting in spitting up phlegm. A non-productive cough is a dry hacking cough that is usually from an upper respiratory infection or even from a post-nasal drip.
If you have a productive cough, the over the counter medication of choice is Guaifenesin. Guaifenesin is an expectorant whose mechanism of action thins mucus to help bring it out of the respiratory airway. It changes the consistency of the mucus and increases the volume of the sputum. Products available over the counter with this as a primary ingredient include Mucinex and Robitussin.
If you have a dry cough, the over the counter medication of choice is Dextromethorphan. Dextromethorphan is a cough suppressant. It's primary mechanism of action is to increase the cough threshold so that you cough less. Products available with this as a primary ingredient include Delsym and Father John's.
There are several combination products available that have both ingredients. For example Mucinex DM, Robitussin DM, Dayquil and NyQuil products. (Hint: The DM means Dextromethorphan) If you have a productive cough, you should not take a product with a cough suppressant unless absolutely necessary. This is because you may interfere with the amount of sputum that should be expelled. If you are losing sleep because of coughing, then a combination product would be the correct choice for you.
If you are a diabetic, choose cough syrups the are sugar free. For example DiabeticTussin, Robitussin sugar free products, etc.
If you have a post-nasal drip, add an antihistamine, such as Claritin, to your cough medication, as this may likely be the cause of your dry cough.
Lastly, If you have tried these products for at least 3 days with worsening symptoms or no relief, contact your doctor for additional prescription options.