Is There an over the Counter Med I Can Take to Help Reduce Swelling After Filler Injections?

Benadryl and Zyrtec are antihistamines and not diuretics (or waterpills). Unless you have swelling produced by an allergic reaction related to the release of histamine, then antihistamines are not expected to reduce your swelling.  Minimize activity including avoiding bending over at the waist, straining, lifting heavy objects, do ice compresses and consider taking the herb, Arnica montana, which has been shown to reduce the possibility of swelling and bruising.  Some recommend bromelain as well.

Swelling will normally resolve over time on its own. No medication can significantly speed up the process. Some people will recommend homeopathic remedies such as arnica montana and/or bromelain which may or may not be helpful. Applying cold packs and head elevation may help as well. Definitely be careful when applying cold packs and do not apply them directly on the skin to avoid frost bite.

Cooling with ice (never directly on the skin), head elevation, Arnica, Bromelain and Advil after a few days will tend to help with swelling. As this is a physiologic and not an allergic histimine response, Zyrtec and Benedryl (antihistimines) should not have an effect.