Table 1.
Reactions resulting from penicillin allergy evaluations
| Number (%) | All patients (n=509) | Penicillin skin tested patients (n=426) | Direct amoxicillin challenge patients (n=83) | P-value* |
|---|---|---|---|---|
| Adverse drug reactions | 43 (8.5) | 36 (8.5) | 7 (8.4) | 1.0 |
| Hypersensitivity reactions | 26 (5.1) | 21 (4.9) | 5 (6.0) | 0.59 |
| Timing | ||||
| Immediate reaction† | 18 (3.5) | 15 (3.5) | 3 (3.6) | 1.0 |
| Delayed reaction | 8 (1.6) | 6 (1.4) | 2 (2.4) | 0.62 |
| Signs and symptoms‡ | 0.64 | |||
| Itching | 13 (2.6) | 10 (2.4) | 3 (3.6) | 0.45 |
| Rash | 10 (2.0) | 9 (2.1) | 1 (1.2) | 1.00 |
| Erythema | 9(1.8) | 7 (1.6) | 2 (2.4) | 0.64 |
| Flushing | 3 (0.6) | 2 (0.5) | 1 (1.2) | 0.41 |
| Difficulty swallowing | 3 (0.6) | 3 (0.7) | 0 (0.0) | 1.0 |
| Gastrointestinal symptoms | 2 (0.4) | 1 (0.2) | 1 (1.2) | 0.30 |
| Hives | 1 (0.2) | 0 (0.0) | 1 (1.2) | 0.16 |
| Other§ | 6 (1.2) | 5 (1.2) | 1 (1.2) | 1.0 |
| Treatment Administered | ||||
| Antihistamines | 16 (3.1) | 12 (2.8) | 4 (4.8) | 0.31 |
| Corticosteroids | 4 (0.8) | 2 (0.5) | 2 (2.4) | 0.13 |
| Epinephrine | 2 (0.4) | 1 (0.2)‖ | 1 (1.2)¶ | 0.30 |
| Non-hypersensitivity reactions (side effect reactions or subjective symptoms) | 17 (3.3) | 15 (3.5) | 2 (2.4) | 1.0 |
| Signs and symptoms‡ | ||||
| Itching | 9 (1.8) | 8 (1.9) | 1 (1.2) | 1.0 |
| Difficulty swallowing | 5 (1.0) | 4 (0.9) | 1 (1.2) | 0.59 |
| Chest tightness | 2 (0.4) | 2 (0.5) | 0 (0.0) | 1.0 |
| Flushing | 1 (0.2) | 1 (0.2) | 0 (0.0) | 1.0 |
| Gastrointestinal symptoms | 1 (0.2) | 0 (0.0) | 1 (1.2) | 0.16 |
| Allergy documentation | ||||
| Allergy label removed, Initial | 482 (94.7) | 405 (95.1) | 77 (92.8) | 0.42 |
| Allergy label removed, 6 months | 461 (90.6) | 385 (90.4) | 76 (91.6) | 0.73 |
| Erroneous reentry, 6 months | 10 (2.0) | 10 (2.4) | 0 (0.0) | 0.31 |
Chi-squared or Fisher’s Exact test (when expected cell number was less than 5).
Within 4 hours.
Patients could have more than one sign or symptom.
Other included chills, dizziness, headache, lightheadedness, hypertension, and pallor.
Patient had a penicillin rash history and developed dizziness, nausea, erythema, facial pallor and hypertension (155/85mmHg) 10 minutes after ingesting amoxicillin 500mg. Treatments included 0.3 mg IM epinephrine, 25mg diphenhydramine PO, and 40mg prednisone PO. A second dose of epinephrine IM was given for rigors and throat tightness, and symptoms improved 90 minutes later.
Patient had a history of idiopathic anaphylaxis and a remote rash to penicillin. Fifteen minutes after the 500mg dose of amoxicillin, facial hives and hypertension (157/93 mmHg) developed and progressed to involve throat itching and abdominal pain despite cetirizine 20mg PO. Treatment with 0.3 mg IM epinephrine resulted in symptom resolution over the next hour.
Abbreviations: IM, intramuscular; PO per orem