Drilldown: Medicines
Medicines > fda max 
:
10 mg/d (adults) or
3600 mg/day; off-label doses higher are common but bioavailability saturates well below this
& routes:
oral
:
10 mg/d (adults) or
3600 mg/day; off-label doses higher are common but bioavailability saturates well below this
& routes:
oral Use the filters below to narrow your results.
generic:
brand:
classes:
[[:Category:Antiasthmatic_agents|Antiasthmatic]] (1) ·
[[:Category:Anticonvulsants|Anticonvulsant]] (1) ·
[[:Category:Antihistamines|Antihistamine]] (2) ·
[[:Category:Gabapentinoids|Gabapentinoid]] (1) ·
[[:Category:H1_receptor_antagonists|Histamine H1 receptor antagonist (second-generation)]] (2) ·
[[:Category:Leukotriene_receptor_antagonists|Leukotriene receptor antagonist]] (1) ·
[[:Category:Neuropathic pain medicines|Neuropathic pain medicine]] (1)
mechanism:
None (2) ·
'"`UNIQ--vote-00000391-QINU`"' Minimal CYP metabolism; mostly renally cleared unchanged. Cetirizine is the active racemate; levocetirizine is the active R-enantiomer marketed separately'"`UNIQ--ref-00000392-QINU`"'. (1) ·
'"`UNIQ--vote-0000061E-QINU`"' Less reliably anticholinergic than first-generation H1s; minimal antiemetic effect. Desloratadine (Clarinex) is the active enantiomer-of-metabolite version marketed as a Rx alternative. (1)
uses:
'"`UNIQ--vote-00000021-QINU`"', '"`UNIQ--vote-00000022-QINU`"', '"`UNIQ--vote-00000023-QINU`"', '"`UNIQ--vote-00000024-QINU`"', '"`UNIQ--vote-00000025-QINU`"', '"`UNIQ--vote-00000026-QINU`"', '"`UNIQ--vote-00000027-QINU`"', '"`UNIQ--vote-00000028-QINU`"' (1) ·
'"`UNIQ--vote-0000015B-QINU`"', '"`UNIQ--vote-0000015C-QINU`"', '"`UNIQ--vote-0000015D-QINU`"' (1) ·
'"`UNIQ--vote-00000393-QINU`"', '"`UNIQ--vote-00000394-QINU`"', '"`UNIQ--vote-00000395-QINU`"' (1) ·
'"`UNIQ--vote-0000061F-QINU`"', '"`UNIQ--vote-00000620-QINU`"' (1)
starting dose:
10 mg PO once daily (1) ·
10 mg PO once daily (5 mg in older adults or if sedation occurs) (1) ·
10 mg PO once daily in the evening (adults); 4-5 mg in children (1) ·
300 mg PO at bedtime night 1, 300 mg BID day 2, 300 mg TID day 3; titrate to clinical effect, commonly 1800-3600 mg/day divided TID (1)
preparations:
10 mg tablets; 4 mg, 5 mg chewables; 4 mg granules (1) ·
10 mg tablets; 5 mg ODT and chewables; 1 mg/mL oral syrup; combo Claritin-D (with pseudoephedrine, behind-counter) (1) ·
5 mg, 10 mg tablets; 5 mg, 10 mg chewables; 1 mg/mL oral syrup; OTC (1) ·
Capsules 100, 300, 400 mg; tablets 600, 800 mg; oral solution 250 mg/5 mL; Gralise ER tablets 300, 600 mg (once-daily); Horizant ER tablets 300, 600 mg (gabapentin enacarbil, an inactive parent compound metabolized to gabapentin in vivo) (1)
fda max: (Click arrow to add another value)
routes: (Click arrow to add another value)
onset:
halflife:
2.7-5.5 hours'"`UNIQ--ref-0000015E-QINU`"' (1) ·
5-7 hours'"`UNIQ--ref-00000029-QINU`"' (1) ·
8-10 hours (longer in elderly and renal impairment)'"`UNIQ--ref-00000396-QINU`"' (1) ·
~8 hours (parent); ~28 hours (desloratadine, the active metabolite, marketed separately as Clarinex)'"`UNIQ--ref-00000621-QINU`"' (1)
bioavailability:
'''Saturable''' via the LAT-1 amino-acid transporter, producing nonlinear pharmacokinetics: ~60% at 300 mg single dose, falling to ~35% at 1200 mg single dose'"`UNIQ--ref-0000002A-QINU`"' (1) ·
High (oral); not significantly affected by food'"`UNIQ--ref-00000397-QINU`"' (1) ·
High (oral; food prolongs absorption modestly)'"`UNIQ--ref-00000622-QINU`"' (1) ·
~64% (oral; not significantly affected by food)'"`UNIQ--ref-0000015F-QINU`"' (1)
pregnancy:
Generally considered safe; pregnancy registries do not show increased major malformation risk.<sup class="pcp-cn" title="This claim needs a citation.">[[[Pharmacopedia:Citation needed|citation needed]]]</sup> (1) ·
Generally considered safe; widely used. Levocetirizine (the R-enantiomer) is an alternative with similar safety.<sup class="pcp-cn" title="This claim needs a citation.">[[[Pharmacopedia:Citation needed|citation needed]]]</sup> (1) ·
Generally considered safe; widely used. Loratadine and cetirizine are the most-recommended 2nd-gen H1s in pregnancy and lactation.<sup class="pcp-cn" title="This claim needs a citation.">[[[Pharmacopedia:Citation needed|citation needed]]]</sup> (1) ·
Limited human data; some signal for cardiac malformations and developmental delay but confounded by maternal disease and polytherapy.<sup class="pcp-cn" title="This claim needs a citation.">[[[Pharmacopedia:Citation needed|citation needed]]]</sup> (1)
Showing below up to 4 results in range #1 to #4.