- B2 grass pollens
- B3 tree pollens
- B5 weeds and shrub pollen
- bacillus calmette-guerin
- baclofen
- balsalazide disodium
- balsam peru
- bambuterol hydrochloride
- baricitinib
- barium sulfate
- basiliximab
- bazedoxifene acetate
- beclometasone dipropionate
- beclometasone dipropionate monohydrate
- bedaquiline fumarate
- bee venom
- beef insulin
- belatacept
- belimumab
- bendamustine hydrochloride
- bendamustine hydrochloride monohydrate
- bendroflumethiazide
- benperidol
- benralizumab
- benserazide hydrochloride
- Bent pollen (Agrostis tenuis)
- benzalkonium chloride
- benzalkonium chloride solution
- benzocaine
- benzoin sumatra
- benzoyl peroxide
- benzydamine hydrochloride
- benzyl alcohol
- benzyl benzoate
- benzyl cinnamate
- benzylpenicillin sodium
- beractant
- betahistine dihydrochloride
- betaine anhydrous
- betamethasone dipropionate
- betamethasone sodium phosphate
- betamethasone valerate
- betaxolol hydrochloride
- bethanechol chloride
- bevacizumab
- bexarotene
- bezafibrate
- bezlotoxumab
- bicalutamide
- bifonazole
- bilastine
- bimatoprost
- biotin
- birch pollen (Betula spp)
- bisacodyl
- bismuth oxide
- bismuth subgallate
- bismuth subnitrate
- bismuth subsalicylate
- bisoprolol fumarate
- bivalirudin
- black cohosh
- bleomycin sulfate
- blinatumomab
- blue flag
- bortezomib mannitol boronic ester
- bosentan monohydrate
- bosutinib monohydrate
- botulinum toxin type a
- botulinum toxin type b
- bovine insulin
- brentuximab vedotin
- brimonidine tartrate
- brinzolamide
- brivaracetam
- brodalumab
- Brome pollen (Bromus spp)
- bromfenac sodium sesquihydrate
- bromocriptine mesilate
- buclizine hydrochloride
- budesonide
- bumetanide
- bupivacaine hydrochloride
- bupivacaine hydrochloride anhydrous
- buprenorphine
- buprenorphine hydrochloride
- bupropion hydrochloride
- burdock root liquid extract
- burdock root powder
- buserelin acetate
- buspirone hydrochloride
- busulfan
- butternut bark
