Codeine and hydrocodone are the two strongest narcotic cough syrups available in the United States. Since they are considered to be narcotic drugs, they are only available with a prescription from a doctor.
Doctors generally only prescribe narcotic cough medications to people who have been suffering with a cough for a long period of time. The narcotics that are present in the cough syrups allow a person to relax and can help them sleep undisturbed by coughing. Since these medications contain narcotics, they should always be taken under the supervision of a doctor and should not be used for purposes other than what they were prescribed.
There is a slight risk for addiction in people who take narcotic cough syrup. People can become physically dependent on the drug and their bodies may not be able to stop coughing without the drug. Narcotic cough syrups may also interfere with other medications, especially anti-anxiety and antidepressant medications. Narcotic medications nearly always make patients feel drowsy and can cause confusion. People who are taking narcotic cough syrup should not drive or operate machinery when they are under the influence of the drug.