Difference Between Ephedrine and Pseudoephedrine (With Table)

Pharmaceutical products are medicines used to cure and treat diseases. From ancient times to the modern world, they have cured innumerable patients. The medicines or drugs coming beneath it are classified in many categories based on their uses and target mechanism etc. 

These medicines or drugs may be natural based or chemically prepared according to their site of action and strong or weak action.

Ephedrine vs Pseudoephedrine

The difference between Ephedrine and Pseudoephedrine is that Ephedrine both differ in their configuration. According to the Wedge and Dash formula, the hydroxyl group (-OH) present in the molecular structure of Ephedrine and Pseudoephedrine are different. In ephedrine, the hydroxyl group (-OH) is present towards the reader (in the plane), while the hydroxyl group (-OH) present in the pseudoephedrine is away from the reader (out of the plane). Therefore, they are also known as cis and trans isomers of each other.

Ephedrine is a traditional Chinese pharmaceutical medicine which is used to cure asthma and bronchitis in patients for centuries. Ephedrine is bronchodilator medicine and is highly effective. It also helps in increasing the blood pressure of the patient. It does work as an anesthetic drug. The drug can be taken by oral means or by injecting into the muscle, vein, or under the skin.

Pseudoephedrine is also a traditional Chinese medicine which is used to cure asthma and bronchitis for centuries. Pseudoephedrine is also a bronchodilator and is less effective. It also has less effective in helping in increasing the blood pressure of the patient. It can be used for nasal congestion.  

Comparison Table Between Ephedrine and Pseudoephedrine

Parámetros de comparaciónEphedrinePseudoephedrine
Hydroxyl group (-OH) ConfigurationThe Hydroxyl group is present towards the reader.Hydroxyl group is present away the reader.
RIS Configuration 1R, 2S1S, 2S
Adrenergic Receptor ActivityEphedrine directly acts on adrenergic receptors with strong action.Pseudoephedrine directly acts on adrenergic receptors with a weak action.
Indirect Activity Ephedrine also acts by displacing norepinephrine from storage vesicles.It mainly acts by displacing norepinephrine from storage vesicles indirectly.
Chemical Activity Mixed acting sympathomimetic amineIndirectly acting sympathomimetic amine.
Clinical UseAnaesthesia induced hypotension drugNasal decongestant drug

What is Ephedrine?

Ephedrine is a traditional Chinese medicine to cure asthma and bronchitis for centuries. Ephedrine is a stimulant and is used to increase blood pressure within them during spinal anesthesia. Sometimes it is seen that this drug is being used to treat narcolepsy (the sleepwalk cycle) and obesity, but it is not a preferred drug for the same.

Ephedrine medicine is found in the plant named “Ephedra” it is a type of gymnosperm. It was first isolated in the year 1885, and the medicine came into the market in the year 1926 for its commercial use. The medicine has been considered as the generic medicine and is listed on the World Health Organization’s List of Essential Medicine.

The structural formula of the drug is C10H15NO. According to Wedge and Dash formula, the hydroxyl group (-OH) present in the molecule is towards the reader, which means it is in the plane.

The intake of medicine can be done orally by injecting in the muscles, venas, or under the skin. The effect of the medicine, if taken orally, lasts up to 4hours, and by injecting it lasts up to 1hour.

Some of the side effects are listed which has been commonly observed within the patients are – hallucinations, anxiety, disturbed sleep, headache, increased blood pressure, loss of appetite, etc. 

What is Pseudoephedrine?

Pseudoephedrine is a medicine traditionally used in China for the treatment of asthma and bronchitis for centuries. It is also a stimulant and is quite less effective in increasing the blood pressure of the patient. It is also a bronchodilator. The pseudoephedrine medicine is mainly used as a nasal decongestant to treat sinuses and wakefulness-promoting drugs (increasing alertness).

It is also isolated from the same plant as ephedrine as an alkaloid. But in Ephedra Vulgaris, the medicine is present along with ephedrine, but the majority of the medicine is produced commercially. 

The medicine is produced with the help of yeast. This is done by fermenting yeast by dextrose in the presence of benzaldehyde. And later, the final product is formed via reductive amination. The medicine is produced in bulk in India and China which has favorable economic and industrial conditions for its mass export. 

The molecular formula of Pseudoephedrine medicine is the same as ephedrine that is C10H15NO. The hydroxyl group (-OH) present in the molecule is present away from the reader, which means it is present out of the plane. This is explained based on the Wedge and Dash formula. Thus, pseudoephedrine and ephedrine are considered to be the cis and transforms of each other. 

Main Differences Between Ephedrine and Pseudoephedrine

  1. In the configuration of Ephedrine, the hydroxyl group (-OH) present in it is present towards the reader, whereas the hydroxyl group (-OH) of the Pseudoephedrine is present away from the reader. This configuration is based on Wedge and Dash formula. 
  2. The RIS Configuration of ephedrine is 1R, 2S, while the RIS Configuration of the pseudoephedrine is 1S, 2S.
  3. Ephedrine is said to be directly acting on the adrenergic receptors with strong actions, while Pseudoephedrine also directly acts on the adrenergic receptors but with mild action.
  4. Ephedrine directly acts and displaces the norepinephrine from the storage vesicles, while Pseudoephedrine also acts and displaces the norepinephrine from the storage vesicles, but the way of action is indirect.
  5. Ephedrine is a mixed-acting sympathomimetic amine, while Pseudoephedrine is an indirectly-acting sympathomimetic amine.
  6. The clinical use of Ephedrine is that it is an anesthesia-induced hypotension drug, while Pseudoephedrine is a nasal decongestant drug. 

Conclusión

The pharmaceutical field has undoubtedly grown in the past few decades. Now, we have medicines and drugs to cure patients of the most severe diseases. Our scientists and biologists are doing commendable work towards mankind.

Ephedrine and Pseudoephedrine are the drugs which were developed in the ancient times when there weren’t many sources available to the scientist. They were used as an anesthetic and nasal decongestant. Both the medicines work on adrenergic receptors with strong and weak modes of action.

Ephedrine acts directly in displacing norepinephrine from the storage vesicles, whereas pseudoephedrine contrastingly indirectly acts on it. Ephedrine is a mixed-acting sympathomimetic amine, while pseudoephedrine is an indirectly acting sympathomimetic amine.

Referencias

  1. https://onlinelibrary.wiley.com/doi/abs/10.1111/1556-4029.14015
  2. https://journals.lww.com/anesthesia-analgesia/fulltext/2003/11000/The_Sympathomimetic_Actions_of_l_Ephedrine_and.5.aspx
  3. https://pubs.acs.org/doi/pdf/10.1021/ja00213a033