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New
Options For HRT Provide Lower Doses Of Hormones
For women who require hormone replacement therapy (HRT)
to relieve menopausal symptoms such as hot flashes, night
sweats, and vulvar and vaginal atrophy, the FDA advises
using the lowest dose for the shortest duration necessary.
Two new low-dose options are now available.
One
is an estradiol acetate vaginal ring (Femring) that is
self-inserted into the vagina once every three months.
The ring delivers a steady dose of estradiol estrogen
at 0.05 mg or 0.1 mg per day. In trials, headache, intermenstrual
bleeding, vaginal candidiasis, and breast tenderness were
the most common adverse events.
The
FDA also approved a low-dose form of Prempro containing
0.45 mg of conjugated estrogens and 1.5 mg of medroxyprogesterone
acetate per tablet. The full-dose forms of Prempro have
0.625 mg of estrogen and either 2.5 or 5 mg of the progestin.
The 0.625/2.5 formulation was used in the Women's Health
Initiative, a large trial in which estrogen/ progestin
was linked to an increased risk of breast cancer and cardiovascular
and venous thromboembolic events.
U.S.
Food and Drug Administration. "FDA approves lower
dose of Prempro, a combination estrogen and progestin
drug for postmenopausal women." 2003. www.fda.gov/bbs/topics/news/2003/new00878.html
(17 Mar. 2003).
Galen
Holdings PLC. "Femring receives FDA approval."
2003. www.galenplc.com/investor/press/displaypress.asp?id=1172
(26 Mar. 2003).
Reducing
Drug Errors In Kids Calls For Extra Precautions
Because pediatric dosages are often based on weight and
may require converting pounds to kilograms, there's more
room for error when medications are given to children.
According to recently issued recommendations from the
U.S. Pharmacopeia (USP), clinicians can take advantage
of a number of measures to prevent such errors. These
include computer-automated calculations, strict protocols
for verifying dosage accuracy, and the use of unit-dose
or unit-of-use containers.
In
addition, the USP says that a child's weight, age, and
other appropriate data should be clearly identified on
all prescriptions and orders before being dispensed or
administered. For more on the USP's recommendations, visit
www.usp.org and click on "Practitioner Reporting."
U.S.
Pharmacopeia. "USP issues recommendations for preventing
medication errors in children." 2003. www.onlinepressroom.net/uspharm
(22 Jan. 2003).
Low-Intensity
Warfarin Shows Promise For Long-Term Use
Researchers called an early halt to a study on warfarin
sodium (Coumadin) as evidence emerged of significant benefits
from a long-term, low-intensity regimen for preventing
recurrent venous thromboembolism (VTE). The low-intensity
regimen had a target international normalized ratio (INR)
of 1.5 - 2.0 rather than the standard target of 2.0 -
3.0. Maintaining that standard INR requires higher doses
of warfarin, which are associated with substantial risk
of major hemorrhage in long-term use.
The
trial was to run until 2005 but was halted after 508 patients
had been followed for an average of two years. Researchers
found that the use of low-intensity warfarin reduced a
patient's risk of VTE by 64% when compared to patients
taking placebo. No significant difference was seen in
the occurrence of major hemorrhage among patients on placebo
vs. those on warfarin. Researchers also found that patients
on the low-intensity warfarin had a 48% reduction in their
risk of a combination of events that included recurrent
VTE, major hemorrhage, and death.
Ridker,
P. M., Goldhaber, S. Z., et al. (2003). Long-term, low-intensity
warfarin therapy for the prevention of recurrent venous
thromboembolism. N Engl J Med, http://content.nejm.org/cgi/content/abstract/NEJMoa035029v1
(25 Feb. 2003).
A
Brand New Therapy For Psoriasis Sufferers
The FDA has approved a new immunosuppressive therapy that
blocks and reduces the overactive T cells that play a
significant role in the development of psoriasis. The
new drug, alefacept (Amevive), is administered weekly
IM or IV for 12 weeks. It is indicated for adults with
moderate-to-severe chronic plaque psoriasis who are candidates
for systemic therapy or phototherapy.
Alefacept
was evaluated against placebo in a study of more than
1,000 patients. The drug produced significantly greater
reductions in the surface area of skin affected and in
the severity of scaling and inflammation. These improvements
were linked to a reduction in T cells.
Because
alefacept suppresses the immune system, it can increase
the risk of malignancies and infection. Patients' CD4+
T-lymphocyte counts must be monitored weekly during the
12-week treatment and used to guide dosing. The drug shouldn't
be used in patients with a history of systemic malignancies
or those with a clinically important infection.
U.S.
Food and Drug Administration. "FDA approves first
biologic therapy for psoriasis." 2003. www.fda.gov/bbs/topics/answers/2003/ans01194.html
(6 Feb. 2003).
Biogen,
Inc. "New Amevive (alefacept)." 2003. www.amevive.com
(6 Feb. 2003).
Drug
Roundup
*The CDC has warned that individuals diagnosed with heart
disease shouldn't receive the smallpox vaccine at this
time. Among the more than 25,000 civilians who've received
the vaccine, several cases of cardiac problems-including
fatal MI-have occurred and are being investigated to determine
if the vaccine is a cause.
*The
FDA has approved pegvisomant (Somavert), a new class of
drug, for treating acromegaly, a disorder in which excess
growth hormone causes enlargement of distal portions of
the skeleton. The disorder can lead to life-threatening
heart and respiratory disease.
*CBS
News has reported that a variety of psychiatric symptoms,
ranging from anxiety to psychotic behavior, have been
linked to mefloquine HCl (Lariam), which is used for the
prevention and treatment of malaria. The drug's prescribing
information indicates that it shouldn't be used in patients
with a history of psychiatric disorders. Also, it should
be discontinued if a patient develops acute anxiety, depression,
restlessness, or confusion.
Problem
Rx
Are These Symptoms Of CAD, Or A Drug Side Effect? A 74-year-old
man with mild Alzheimer's is admitted for an evaluation
of dizzy spells. While on telemetry, he complains of dizziness,
and the cardiac monitor indicates a brief episode of bradycardia
at 38 bpm and first-degree heart block. What kind of follow
up is required? Though it might sound as if this patient
needs a pacemaker, medication side effects need to be
ruled out. In this case, the patient has been taking donepezil
HCl (Aricept) 10 mg PO at bedtime for his Alzheimer's
symptoms. Donepezil can have vagotonic effects in the
sinoatrial and atrioventricular nodes-which may cause
bradycardia and heart block in patients with or without
underlying cardiac conduction abnormalities. The cardiologist
stopped the donepezil. Four days later, the patient was
asymptomatic, and his heart had returned to a normal sinus
rhythm. THE AUTHOR LINDA M. PORTERFIELD, RN, PhD, is a
clinical pharmacologist and director of cardiovascular
research at Arrhythmia Consultants in Memphis. She works
with her husband, James Porterfield, MD, FACC, who is
a cardiologist and electrophysiologist.
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