The present disclosure relates to compounds and methods which may be useful as inhibitors of H4R for the treatment or prevention of inflammatory, autoimmune, allergic, and ocular diseases. Compounds of the disclosure include: 5-(Piperazin-1-yl)-8-(thiophen-2-yl)tetrazolo[1,5-c]pyrimidine and 5-(Piperazin-1-yl)-8-(thiophen-3-yl)tetrazolo[1,5-c]pyrimidine