Table 3.
Pharmacokinetics and pharmacodynamics of some antihistamines in adults.11
| Generation | Tmax (h) | Half-life (h) | Start of action (h) | Duration of effect (h) | |
|---|---|---|---|---|---|
| Chlorpheniramine | 1st | 2.8 | 27.9 | 3 | 24 |
| Diphenhydramine | 1st | 1.7 | 9.2 | 2 | 12 |
| Hydroxyzine | 1st | 2.1 | 20.0 | 2 | 24 |
| Bilastine | 2nd | 1.2 | 14.5 | 2 | 24 |
| Cetirizine | 2nd | 1.0 | 6.5 | 0.7 | ≥24 |
| Desloratadine | 2nd | 1–3 | 27 | 2–2.6 | ≥24 |
| Fexofenadine | 2nd | 1–3 | 11 | 1–3 | 24 |
| Levocetirizine | 2nd | 0.8 | 7 | 0.7 | >24 |
| Loratadine | 2nd | 1.2 | 7.8 | 2 | 24 |
| Rupatadine | 2nd | 0.75 | 6 | 2 | 24 |
Adapted from Simons and Simons.2