Can you be allergic to naloxone?

It is possible: It is possible to be allergic to any medication. A medication has other ingredients, such as stabilizers, preservatives, pH buffers, etc..., and a person may be allergic to one of the other ingredients. Also, a person can be ok with the drug, but react to a breakdown product of the drug, or react to a "bound" combination of the drug+substance (the substance may be from the person's own body).

Yes: Allergy has been reported to every single chemical substance known, even with drugs usually used to treat allergy. The allergy is sometimes to something else in the pill or medicine - a preservative, coloring agent or stabilizer. However, without knowing what reaction you had, i can't tell you if its allergy. If you were opiate dependent, and got naloxone, it makes you sick. That is not an allergy.

Hypersensitivity: Per Drugs.com “Allergic reactions including urticaria, rhinitis, dyspnea, Quincke's edema, anaphylactic shock “ are very rare (less than 0.01%) REF: https://www.drugs.com/sfx/naloxone-side-effects.html