Final answer:
Ephedrine, a compound with decongestant properties extracted from the Ephedra plant, is now sold with a prescription due to its chemical structure's similarity to amphetamines and potential side effects. It has a history of medical use dating back thousands of years but is now regulated to prevent misuse. Alternatives like Propylhexedrine are available over-the-counter.
Step-by-step explanation:
Ephedrine is a compound extracted from the Ephedra plant and has been used for over 5000 years to treat conditions such as asthma, hay fever, and congestion due to its decongestant properties. It is chemically similar to adrenaline and has the additional effects of decreasing appetite, increasing blood pressure and heart rate, which led to its use in diet pills. Due to its chemical structure resembling amphetamines, ephedrine can be converted into methamphetamines, which contributed to restrictions being placed on its availability. As a result, products containing ephedrine were reclassified to be sold only with a prescription to help prevent the illicit production of methamphetamines.
Medications containing ephedrine are now tightly regulated, and in many countries, you need a prescription to purchase them. Ephedrine's side effects, including potential for mental health impact such as hallucinations, anxiety, and chemical dependence, have also played a role in it being prescription-only. Alternatives such as Propylhexedrine, found in over-the-counter cold medications like Benzedrex, are used for similar purposes but without necessarily requiring a prescription.