Should people with certain allergies avoid amlodipine?

The package insert for amlodipine advises that people who are allergic to amlodipine should not take it.¹ The manufacturer also says that patients who are hypersensitive to any component of amlodipine should not take it. No other contraindications due to allergies are noted in the prescribing information.

A drug allergy usually refers to a particular type of immune reaction to a drug that is mediated by immunoglobulin E.² These immune-mediated responses to drugs are thought to represent about five to ten percent of all drug reactions and typically occur within hours of initiating a specific medication. Other types of immune hypersensitivity to a drug can be delayed, occurring days to weeks after exposure. There are case reports in the literature of allergic reactions to amlodipine.^3–15

In the follow-up of 999,583 prescriptions of calcium channel blockers, only 46 cutaneous drug reactions were reported.¹⁵ In the same study, three cases of Stevens Johnson syndrome were reported in patients taking amlodipine. The allergic reaction may present as redness, itching, hives, maculopapular or petechial rash, plaques, or hyperkeratosis. Photosensitivity presenting as telangiectasia has also occurred.⁸

Another case report of small bowel angioedema was attributed to taking amlodipine.⁵ The patient experienced abdominal pain, nausea, vomiting, and diarrhea. Abdominal CT confirmed the presence of mural thickening of the intestine. Symptoms subsided after discontinuation of the amlodipine.

^References

1. Norvasc [package insert]. Kirkland, Quebec: Pfizer Labs; 2016.
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3. Baetz BE, Patton M Lou, Guilday RE, Reigart CL, Ackerman BH. Amlodipine-induced toxic epidermal necrolysis. J Burn Care Res 2011; 32 (5): e158-60.
4. Gochoco A, Jones E, Soutendijk C, Alpdogan O, Shi W, Sahu J. Amlodipine-induced hypersensitivity reaction mimicking CD30(+) mycosis fungoides. JAAD Case Reports 2016; 2 (4): 320-322.
5. Turcu AF, White JA, Kulaga ME, Skluth M, Gruss CB. Calcium channel blocker-associated small bowel angioedema. J Clin Gastroenterol 2009; 43 (4): 338-341.
6. Valcarcel Y, Jimenez R, Hernandez V, Aristegui R, Gil A. Efficacy and safety of amlodipine: a comparative study of hypertensive patients treated at primary- and specialised-care centres. Clin Drug Investig 2006; 26 (3): 125-133.
7. Wiwanitkit S, Wiwanitkit V. Oral mucositis, Steven Johnson syndrome and amlodipine usage in a case with metabolic syndrome. Diabetes Metab Syndr 2012; 6 (2): 112.
8. Grabczynska SA, Cowley N. Amlodipine induced-photosensitivity presenting as telangiectasia. Br J Dermatol 2000; 142 (6): 1255-1256.
9. Ioulios P, Charalampos M, Efrossini T. The spectrum of cutaneous reactions associated with calcium antagonists: a review of the literature and the possible etiopathogenic mechanisms. Dermatol Online J 2003; 9 (5): 6.
10. Low L, Zaheri S, Wakelin S. Amlodipine-induced linear IgA disease. Clin Exp Dermatol 2012; 37 (6): 649-651.
11. Murthy MB, Murthy B. Amlodipine-induced petechial rash. J Postgrad Med 2011; 57 (4): 341-342.
12. Orme S, da Costa D. Generalised pruritus associated with amlodipine. BMJ 1997; 315 (7106): 463.
13. Pierce WA, Hederman AD, Gordon CJ, Ostrenga AR, Herrington B. Angioedema associated with dihydropyridine calcium-channel blockers in a child with Burkitt lymphoma. Am J Health Syst Pharm 2011; 68 (5): 402-406.
14. Stern R, Khalsa JH. Cutaneous adverse reactions associated with calcium channel blockers. Arch Intern Med 1989; 149 (4): 829-832.
15. Tuchinda P, Kulthanan K, Khankham S, Jongjarearnprasert K, Dhana N. Cutaneous adverse reactions to calcium channel blockers. Asian Pac J Allergy Immunol 2014; 32 (3): 246-250.