Class
Serotonin agonist
Pharmacodynamics
- Structural analogue of 5-HT
- Selective 5-HT (1D/1B) agonist
- These receptors are found in cerebral and meningeal vessels and mediate vasoconstriction
- May reduce release of calcitonin gene-related peptide and perivascular edema in cerebral circulation
Pharmacokinetics
- Administration: PO, SC, IN, PR
- Bioavailability 15%
- Time to onset: 1.5 hours (0.2 hours for SC)
- Half-life 2 hours
- Short duration of action, often shorter than duration of headache, therefore several doses may be required during prolonged attack
Clinical uses
- First line for acute severe migraine
Adverse effects
- Altered sensations (tingling, warmth)
- Dizziness
- Muscle weakness
- Neck pain
- Injection site reactions with parenteral administration
- Chest discomfort in 1-5%, probably due to coronary vasospasm
Contraindications
- Ischaemic heart disease or angina (due to coronary vasospasm)
- Caution with co-administration of other vasoconstrictors
Further reading
- The Royal Children’s Hospital Melbourne. Clinical Guideline: Headache. RCH
References
- Katzung BG. Basic and Clinical Pharmacology. 14e. 2018: 289-291
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MBBS FACEM DDU (Emergency) CCPU. Emergency Physician in Melbourne, Australia. Co-Ultrasound Lead for Emergency Medicine at The Alfred Hospital. Special interests in diagnostic and procedural ultrasound, medical education, and ECG interpretation. Editor of the LITFL ECG Library.
