J Med Cases

Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Med Cases and Elmer Press Inc

Journal website https://www.journalmc.org

Case Report

Volume 15, Number 8, August 2024, pages 201-207

Navigating Aspirin Hypersensitivity in Patients Undergoing Percutaneous Coronary Intervention

Figure 1. ECG on admission, showing normal sinus rhythm, left ventricular hypertrophy, poor R wave progression. ECG: electrocardiogram.

Figure 2. Coronary angiogram showing severe two-vessel disease with 70-80% occlusion of the mid-LAD and 60-70% occlusion of the proximal LCX. The labeled arrows point to the respective stenotic regions. LAD: left anterior descending artery; LCX: left circumflex artery.

**Table 1.** Aspirin Desensitization Protocol
Step	Day	Time (h)	Aspirin dosage (mg)
The patient underwent a 2-day protocol in which she received three doses of aspirin on the first day, and three more doses on the second day.
1	1	0	20.25 (0.25 tablets)
2	1	3	60.75 (0.75 tablets)
3	1	6	81 (1 tablet)
4	2	0	101.25 (1.25 tablets)
5	2	3	162.5 (2 tablets)
6	2	6	325 (4 tablets)

Table 1. Aspirin Desensitization Protocol

Step

Day

Time (h)

Aspirin dosage (mg)

The patient underwent a 2-day protocol in which she received three doses of aspirin on the first day, and three more doses on the second day.

20.25 (0.25 tablets)

60.75 (0.75 tablets)

81 (1 tablet)

101.25 (1.25 tablets)

162.5 (2 tablets)

325 (4 tablets)

**Table 2.** Protocol for Introducing Low-Dose Aspirin (81 mg) in a Patient With Suspected or Confirmed Aspirin Allergy
Step	Activity
1	Administer 40.5 mg of aspirin and observe for 60 min.
2	Administer 40.5 mg of aspirin and observe for 60 min again. If the patient developed symptoms, repeat this step again.
3	If no symptoms have developed during the first two steps, administer 81 mg of aspirin daily starting the next day.

Table 2. Protocol for Introducing Low-Dose Aspirin (81 mg) in a Patient With Suspected or Confirmed Aspirin Allergy

Step

Activity

Administer 40.5 mg of aspirin and observe for 60 min.

Administer 40.5 mg of aspirin and observe for 60 min again. If the patient developed symptoms, repeat this step again.

If no symptoms have developed during the first two steps, administer 81 mg of aspirin daily starting the next day.

**Table 3.** Protocol for Increasing the Dosage of Aspirin From 81 mg Daily to 325 mg Daily for Loading Purposes in Patients With Suspected or Confirmed Aspirin Allergy
Step	Activity in patients with AERD	Activity in patients without AERD
The use of this protocol assumes that patients are already on an 81 mg dose of aspirin. AERD: aspirin-exacerbated respiratory disease.
1	Administer 121.5 mg of aspirin and observe for 60 min.	Administer 162 mg of aspirin and observe for 60 min.
2	Administer 202.5 mg of aspirin and observe for 60 min.	Administer 325 mg and observe for 60 min.
3	Administer 325 mg aspirin and observe for 180 min.	If no symptoms develop, continue with 325 mg of aspirin starting the next day. Desensitization is complete.
	If no symptoms develop, continue with 325 mg of aspirin starting the next day. Desensitization is complete.	If symptoms develop, treat the symptoms, repeat the same dose, and observe for another 60 min. If no further symptoms, then desensitization is complete and begin 325 mg of aspirin starting the next day.
	If symptoms develop, treat the symptoms, repeat the same dose, and observe for another 60 min. If no further symptoms, then desensitization is complete and begin 325 mg of aspirin starting the next day.

Table 3. Protocol for Increasing the Dosage of Aspirin From 81 mg Daily to 325 mg Daily for Loading Purposes in Patients With Suspected or Confirmed Aspirin Allergy

Step

Activity in patients with AERD

Activity in patients without AERD

The use of this protocol assumes that patients are already on an 81 mg dose of aspirin. AERD: aspirin-exacerbated respiratory disease.

Administer 121.5 mg of aspirin and observe for 60 min.

Administer 162 mg of aspirin and observe for 60 min.

Administer 202.5 mg of aspirin and observe for 60 min.

Administer 325 mg and observe for 60 min.

Administer 325 mg aspirin and observe for 180 min.

If no symptoms develop, continue with 325 mg of aspirin starting the next day. Desensitization is complete.

If symptoms develop, treat the symptoms, repeat the same dose, and observe for another 60 min. If no further symptoms, then desensitization is complete and begin 325 mg of aspirin starting the next day.