Details of Drug Interaction

Details of Drug-Drug Interaction

 Drug General Information (ID: DDINDCIWKZ)
  Drug Name Ondansetron Drug Info Lofexidine Drug Info
  Drug Type Small molecule Small molecule
  Therapeutic Class Antiemetics Antihypertensive Agents
  Structure

 Mechanism of Ondansetron-Lofexidine Interaction (Severity Level: Moderate)
     Additive hypotensive effects Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Ondansetron Lofexidine
      Mechanism 1 Hypotensive effects
Alpha-1 adrenergic receptor  Antagonist 		Hypotensive effects
Alpha-2 adrenergic receptor  Agonist
      Key Mechanism Factor 1
Factor Name Adrenergic receptor alpha-1 Structure Sequence
Protein Family G-protein coupled receptor 1 family
Protein Function
This alpha-adrenergic receptor mediates its action by association with G proteins that activate a phosphatidylinositol-calcium second messenger system. Its effect is mediated by G(q) and G(11) proteins. Nuclear ADRA1A-ADRA1B heterooligomers regulate phenylephrine(PE)-stimulated ERK signaling in cardiac myocytes.
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      Key Mechanism Factor 2
Factor Name Adrenergic receptor alpha-2 Structure Sequence
Protein Family G-protein coupled receptor 1 family
Protein Function
Alpha-2 adrenergic receptors mediate the catecholamine-induced inhibition of adenylate cyclase through the action of G proteins. The rank order of potency for agonists of this receptor is oxymetazoline > clonidine > epinephrine > norepinephrine > phenylephrine > dopamine > p-synephrine > p-tyramine > serotonin = p-octopamine. For antagonists, the rank order is yohimbine > phentolamine = mianserine > chlorpromazine = spiperone = prazosin > propanolol > alprenolol = pindolol.
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      Mechanism Description
  • Additive hypotensive effects by the combination of Ondansetron and Lofexidine 
     Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Ondansetron Lofexidine
      Mechanism 2 Prolong QT interval Prolong QT interval
      Key Mechanism Factor 3
Factor Name QT interval
Factor Description Long QT syndrome is a heart signaling disorder that can cause a fast, chaotic heartbeat (arrhythmia). Many people may not exhibit symptoms, and usually the condition is detected during routine medical tests. In others, the most common symptoms include: sudden fainting, palpitations, dizziness, seizures, sudden death.
      Mechanism Description
  • Increased risk of prolong QT interval by the combination of Ondansetron and Lofexidine 

Recommended Action
      Management Caution is recommended if lofexidine is used in combination with other drugs that can prolong the QT interval. Periodic monitoring with on-treatment electrocardiograms and serum electrolytes (magnesium, potassium) should be considered. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.

References
1 Canadian Pharmacists Association.
2 Cerner Multum, Inc. "Australian Product Information.".
3 Cerner Multum, Inc. "UK Summary of Product Characteristics.".
4 Product Information. Lucemyra (lofexidine). US WorldMeds LLC, Louisville , KY.
5 EMA. European Medicines Agency. European Union "EMA - List of medicines under additional monitoring.".