Topic 5 in new 2020 asthma guidelines addresses use of allergen immunotherapy specifically for treatment of asthma.

This includes allergy shots (subcutaneous immunotherapy or SCIT) and sublingual drops (SLIT).

Full guidelines found here: https://www.nhlbi.nih.gov/health-topics/all-publications-and-resources/2020-focused-updates-asthma-management-guidelines

Both allergy shots and drops work well for treating allergic rhinitis. Both can desensitize & induce tolerance while reducing symptoms & need for medication. Neither works immediately. Both have pros/cons to consider.

@EAACI_HQ has great info on this: https://onlinelibrary.wiley.com/doi/full/10.1111/all.13317

New 2020 asthma guidelines recommend considering allergy shots for those with persistent asthma who have:
-Recurrent symptoms with exposure
-Failed/don't want medications
-Understand risks/benefits

Need to have well controlled asthma to reduce risk for shot reactions

Allergy shots should never be administered at home due to risk for anaphylaxis.

Asthma must be assessed prior to each injection, which should be given at a doctor's office, followed by observation for 30 minutes.

Based upon published data at time of systematic review for the 2020 asthma guidelines, the evidence does not support using sublingual immunotherapy (SLIT) specifically for treatment of allergic asthma.

This is DIFFERENT than using it to treat allergic rhinitis, which can help.