Calagel contains diphenhydramine hydrochloride and zinc acetate so I would suggest using only one brand of product so you do not overdose.

Tecnu Extreme is a cleanser that also contains a homeopathic anti-itch ingredient, grindelia robusta. Tecnu Extreme can be followed by the anti-itch medication of your choice but you may find you do not need anything else.

See:

Calagel drug facts

Tecnu Extreme drug facts