A large majority of the medicines that are most widely advertised to cure all sorts of pains and aches contain some form of narcotic--most commonly either alcohol or opium.

The reason for this is that no one medicine can possibly be a cure for all sorts of diseases; and the only kind of medicine that will make almost every one who takes it feel a little bit better for the time being is a narcotic, because it has the power of deadening the nerves to pain or discomfort.
Careful analyses by boards of health and government chemists of a great number of advertised medicines have shown that three-fourths of the so-called tonics and "bitters" and "bracers" of all sorts contain alcohol--some of them in such large amounts as to be stronger and more intoxicating than whiskey.

The same investigations have found that a large majority of the "colic cures," "pain relievers," nearly all the "soothing syrups" and "teething syrups," and most of the cough mixtures, cough cures, and consumption cures contain opium, often in quite dangerous amounts.

The widely-advertised medicines and remedies guaranteed to cure all sorts of diseases in a very short time are almost certain to be one of two things: either out-and-out frauds, costing about four cents a bottle and selling for fifty cents or a dollar, or else dangerous poisons.

All patent pain relievers are safe things to let entirely alone.
Another risk in taking medicines wholesale, especially those that are known as patent medicines, is that you never can be quite sure what you are taking, as their composition is usually kept a strict secret.