Difference Between Clonazepam and Lorazepam

From the IUPAC name, Clonzapam and Lorazepam shows some differences between them. Clonazepam and Lorazepam are two drugs belonging to the drug family of benzodiazepines, which acts on brain chemicals when they are in imbalance. Benzodiazepines act on GABA receptors in the brain and enhance the neurotransmitter GABA; the chief inhibitory neurotransmitter.

What is Clonazepam?

Clonazepam is the generic name of the drug we come across under trade names such as Rivotril, Linotril, Clonotril, and Klonopin. Clonazepam is a drug commonly prescribed for epilepsy, seizures, and panic disorders. This is a short-term treatment drug because patients tend to develop tolerance to the drug over a long period of usage. It has been reported that Clonazepam causes adverse effects such as drowsiness and motor impairment. Clonazepam could be harmful if a person has a medical history of kidney or liver disease, asthma, depression, drug or alcohol addiction. It is also advisable to avoid usage during pregnancy as it causes harm to unborn baby.

Clonazepam comes in a disintegrating tablet. The patient should be closely monitored, and tested to make sure the liver function is proper. The drug should not be continued for more than nine months, and sudden withdrawal of the drug may cause discomfort.

What is Lorazepam?

Lorazepam is also commonly known as Ativan or Orfidal. This is commonly prescribed for anxiety disorders. Similar to Clonazepam, Lorazepam is also a short term treatment drug. In addition to anxiety disorders, Lorazepam can be used in treating insomnia and acute seizures. Lorazepam has a relatively high physical addiction effect. It should not be continued for more than four months in use. Lorazepam like Clonazepam, could be harmful to people with medical conditions such as kidney or liver disease, asthma, depression, drug or alcohol addiction. Lorazepam causes side effects such as drowsiness, muscle weakness, confusion and hallucinations, etc.

What is the difference between Clonazepam and Lorazepam?

• IUPAC Name:

• Clonazepam has the IUPAC name 5-(2-Chlorophenyl)-7-nitro-2,3-dihydro-1,4-benzodiazepin-2-one.

• Lorazepam has the IUPAC name (RS)-7-Chloro-5-(2-chlorophenyl)-3-hydroxy-1,3-dihydro-2H-1,4-benzodiazepin-2-one.

• Structural Difference:

• The structural difference between the two is where Clonazepam has a nitro group, Lorazepam has a Chloride group.

• Physical Addiction:

• Lorazepam has a higher physical addiction potential than Clonazepam.

• Diseases:

• Lorazepam is used for anxiety disorders, insomnia, and acute seizures.

• Clonazepam is used for epilepsy, seizures, and panic disorders.

Disclaimer: This is only a guide to differentiate certain characteristics between the two drugs mentioned. Do not use this as a medical guide. If you are looking for more than information, please seek advice from a qualified doctor.


Images Courtesy:

  1. Clonazepam Pills by ParentingPatch (CC BY-SA 3.0)
  2. Lorazepam 0.5mg Tablets via Wikicommons (Public Domain)