19
Î Second-generation antihistamines are safe and effective therapies in
patients with CU and are considered first-line agents. (A)
Î Higher doses of second-generation antihistamines might provide more
efficacy, but data are limited and conflicting for certain agents. (B)
Î First-generation antihistamines have proved efficacy in the treatment
of CU. Efficacy of first-generation antihistamines is similar to that of
second-generation antihistamines, but sedation and impairment are
greater with first-generation antihistamines, especially with short-
term use. (A) First-generation antihistamines can be considered in
patients who do not achieve control of their condition with higher-dose
second-generation antihistamines. (D)
H
2
–Antihistamines
Î H
2
-antihistamines taken in combination with first- and second-
generation H
1
-antihistamines have been reported to be more
efficacious compared with H
1
-antihistamines alone for the
treatment of CU. (A) However, this added efficacy might be related
to pharmacologic interactions and increased blood levels of first-
generation antihistamines. (B) Because these agents are well
tolerated, the addition of H
2
-antagonists can be considered when
CU is not optimally controlled with second-generation antihistamine
monotherapy. (D)
Î Leukotriene receptor antagonists have been shown in several, but
not all, randomized controlled studies to be efficacious in patients
with CU. (A) Leukotriene receptor antagonists are generally well
tolerated (A). Leukotriene receptor antagonists can be considered for
patients with CU with unsatisfactory responses to second-generation
antihistamine monotherapy.
Antidepressants With H
1
- And H
2
-Antagonist Activity
Î Doxepin: Treatment with hydroxyzine or doxepin can be considered
in patients whose symptoms remain poorly controlled with dose
advancement of second-generation antihistamines and the addition
of H
2
-antihistamines, first-generation H
1
-antihistamines at bedtime,
and/or antileukotrienes. (D)
Systemic Corticosteroids
Î Systemic corticosteroids are frequently used in patients with
refractory CU, but no controlled studies have demonstrated efficacy.
In some patients short-term use (e.g., 1–3 weeks' duration) might be
required to gain control of their symptoms until other therapies can
achieve control. Because of the risk of adverse effects with systemic
corticosteroids, long-term use for treatment of patients with CU
should be avoided as much as possible. (D)
