Prazosin


Prazosin is a derivative of quinazoline. It is an antihypertensive drug that produces vasodilatation by blocking post-synaptic alpha receptors.
 
Incidence
Urticaria: 0.3% of subjects treated.
 
Anaphylactic shock: one case reported.
 
Clinical manifestations
General: anaphylactic shock
 
Cutaneous: urticaria, angioedema.
 
Respiratory: bronchospasm.
 
Diagnostic methods
Cutaneous testing: prick tests are very hazardous (one collapse reported).
 
No specific IgE found.
 
Mechanisms
Undetermined.
 
Management
Avoidance.

References

  1. Chodosh S, Tuck J, Pizzuto D, "Prazosin in hypertensive patients with chronic bronchitis and asthma: a brief report", Am. J. Med., 1989; 86 (1 B): 91-3
  2. Ruzicka T, Ring J, "Hypersensitivity to prazosin", Lancet, 1983; 1 (8322): 473-4.

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.