Antihistamines (Systemic)
Proper Use of This MedicineAntihistamines are used to relieve or prevent the symptoms of your medical
problem. Take them only as directed. Do not take more of them and do not take
them more often than recommended on the label, unless otherwise directed by
your doctor. To do so may increase the chance of side effects
.
Dosing - The dose of an antihistamine will be different
for different patients. Follow your doctor's orders or
the directions on the label
. The following information includes only
the average doses of antihistamines. If your dose is
different, do not change it
unless your doctor tells you to do so. The number of capsules or tablets or teaspoonfuls of liquid that you take
or the number of suppositories you use depends on the strength of the medicine.
Also, the number of doses you take each day and the time
between doses depends on whether you are taking a short-acting or long-acting
form of antihistamine
.
-
For use as an antihistamine:
-
For azatadine
-
For oral
dosage form (tablets):
-
Adults: 1 to 2 milligrams (mg) every eight to twelve hours as needed.
-
Children younger than 12 years of age: Use and dose must be determined
by your doctor.
-
Children 12 years of age and older: 0.5 mg to 1 mg two times a day
as needed.
-
For brompheniramine
-
For regular (short-acting) oral
dosage
forms (capsules, tablets, or liquid):
-
Adults and teenagers: 4 milligrams (mg) every four to six hours as
needed.
-
Children 2 to 6 years of age: 1 mg every four to six hours as needed.
-
Children 6 to 12 years of age: 2 mg every four to six hours as needed.
-
For injection
dosage form:
-
Adults and teenagers: 10 milligrams (mg) injected into a muscle,
under the skin, or into a vein every eight to twelve hours.
-
Children younger than 12 years of age: 0.125 mg per kilogram (0.06
mg per pound) of body weight injected into a muscle, under the skin, or into
a vein three or four times a day as needed.
-
For cetirizine
-
For oral
dosage forms (syrup and tablets):
-
Adults: 5 to 10 milligrams (mg) once a day.
-
Children younger than 2 years of age: Use and dose must be determined
by your doctor.
-
Children 2 to 6 years of age: 2.5 mg once a day, up to a maximum
of 5 mg once a day or 2.5 mg twice a day.
-
Children 6 years of age and older: 5 to 10 mg once a day.
-
For chlorpheniramine
-
For regular (short-acting) oral
dosage
forms (tablets or liquid):
-
Adults and teenagers: 4 milligrams (mg) every four to six hours as
needed.
-
Children younger than 6 years of age: Use and dose must be determined
by your doctor.
-
Children 6 to 12 years of age: 2 mg three or four times a day as
needed.
-
For long-acting oral
dosage forms (capsules
or tablets):
-
Adults: 8 or 12 milligrams (mg) every eight to twelve hours as needed.
-
Children younger than 12 years of age: Use and dose must be determined
by your doctor.
-
Children 12 years of age and older: 8 mg every twelve hours as needed.
-
For injection
dosage form:
-
Adults: 5 to 40 milligrams (mg) injected into a muscle, into a vein,
or under the skin.
-
Children: 0.0875 mg per kilogram (0.04 mg per pound) of body weight
injected under the skin every six hours as needed.
-
For clemastine
-
For oral
dosage forms (tablets or liquid):
-
Adults and teenagers: 1.34 milligrams (mg) two times a day or 2.68
mg one to three times a day as needed.
-
Children younger than 6 years of age: Use and dose must be determined
by your doctor.
-
Children 6 to 12 years of age: 0.67 to 1.34 mg two times a day.
-
For cyproheptadine
-
For oral
dosage forms (tablets or liquid):
-
Adults and children 14 years of age and older: 4 milligrams (mg)
every eight hours. The doctor may increase the dose if needed.
-
Children 2 to 6 years of age: 2 mg every eight to twelve hours as
needed.
-
Children 6 to 14 years of age: 4 mg every eight to twelve hours as
needed.
-
For desloratadine
-
For oral
dosage form (tablets):
-
Adults and children 12 years of age and older: 5 milligrams (mg)
once a day.
-
Children younger than 12 years of age: Use and dose must be determined
by your doctor.
-
For dexchlorpheniramine
-
For regular (short-acting) oral
dosage
forms (tablets or liquid):
-
Adults and teenagers: 2 milligrams (mg) every four to six hours as
needed.
-
Children 2 to 5 years of age: 0.5 mg every four to six hours as needed.
-
Children 5 to 12 years of age: 1 mg every four to six hours as needed.
-
For long-acting oral
dosage form (tablets):
-
Adults: 4 or 6 milligrams (mg) every eight to twelve hours as needed.
-
Children: Use and dose must be determined by your doctor.
-
For diphenhydramine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults and teenagers: 25 to 50 milligrams (mg) every four to six
hours as needed.
-
Children younger than 6 years of age: 6.25 to 12.5 mg every four
to six hours.
-
Children 6 to 12 years of age: 12.5 to 25 mg every four to six hours.
-
For injection
dosage form:
-
Adults: 10 to 50 milligrams (mg) injected into a muscle or into a
vein.
-
Children: 1.25 mg per kg (0.6 mg per pound) of body weight injected
into a muscle four times a day.
-
For doxylamine
-
For oral
dosage form (tablets):
-
Adults and teenagers: 12.5 to 25 milligrams (mg) every four to six
hours as needed.
-
Children younger than 6 years of age: Use and dose must be determined
by your doctor.
-
Children 6 to 12 years of age: 6.25 to 12.5 mg every four to six
hours as needed.
-
For fexofenadine
-
For oral
dosage forms (capsules):
-
Adults and teenagers: 60 milligrams (mg) two times a day as needed
or 180 mg once a day
-
Children 6 to 11 years of age: 30 mg twice a day as needed.
-
Children under 6 years of age: Use and dose must be determined by
your doctor.
-
For loratadine
-
For oral
dosage forms (tablets or liquid):
-
Adults and children 6 years of age and older: 10 milligrams (mg)
once a day.
-
Children 2 to 5 years of age: 5 mg once a day.
-
For phenindamine
-
For oral
dosage form (tablets):
-
Adults and teenagers: 25 milligrams (mg) every four to six hours
as needed.
-
Children younger than 6 years of age: Use and dose must be determined
by your doctor.
-
Children 6 to 12 years of age: 12.5 mg every four to six hours as
needed.
-
For nausea, vomiting, and vertigo (only dimenhydrinate and diphenhydramine
are used for vertigo):
-
For dimenhydrinate
-
For regular (short-acting) oral
dosage
forms (tablets or liquid):
-
Adults and teenagers: 50 to 100 milligrams (mg) every four to six
hours as needed.
-
Children 2 to 6 years of age: 12.5 to 25 mg every six to eight hours
as needed.
-
Children 6 to 12 years of age: 25 to 50 mg every six to eight hours
as needed.
-
For long-acting oral
dosage form (capsules):
-
Adults: 1 capsule (contains 25 milligrams [mg] for immediate action
and 50 mg for long action) every twelve hours.
-
Children: Use and dose must be determined by your doctor.
-
For injection
dosage form:
-
Adults: 50 milligrams (mg) injected into a muscle or into a vein
every four hours as needed.
-
Children: 1.25 mg per kg (0.6 mg per pound) of body weight injected
into a muscle or into a vein every six hours as needed.
-
For suppository
dosage form:
-
Adults: 50 to 100 milligrams (mg) inserted into the rectum every
six to eight hours as needed.
-
Children younger than 6 years of age: Use and dose must be determined
by your doctor.
-
Children 6 to 8 years of age: 12.5 to 25 mg inserted into the rectum
every eight to twelve hours as needed.
-
Children 8 to 12 years of age: 25 to 50 mg inserted into the rectum
every eight to twelve hours as needed.
-
Children 12 years of age and older: 50 mg inserted into the rectum
every eight to twelve hours as needed.
-
For diphenhydramine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults: 25 to 50 milligrams (mg) every four to six hours as needed.
-
Children: 1 to 1.5 mg per kg (0.45 to 0.7 mg per pound) of body weight
every four to six hours as needed.
-
For injection
dosage form:
-
Adults: 10 milligrams (mg) injected into a muscle or into a vein.
Dose may be increased to 25 to 50 mg every two to three hours.
-
Children: 1 to 1.5 mg per kg (0.45 to 0.68 mg per pound) of body
weight injected into a muscle every six hours.
-
For hydroxyzine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults: 25 to 100 milligrams (mg) three or four times a day as needed.
-
Children younger than 6 years of age: 12.5 mg every six hours as
needed.
-
Children 6 years of age and older: 12.5 to 25 mg every six hours
as needed.
For injection
dosage form:
-
Adults: 25 to 100 milligrams (mg) injected into a muscle.
-
Children: 1 mg per kg (0.45 mg per pound) of body weight injected
into a muscle.
-
For Parkinson's disease:
-
For diphenhydramine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults: 25 milligrams (mg) three times a day when starting treatment.
Your doctor may increase the dose gradually later if needed.
-
For injection
dosage form:
-
Adults: 10 to 50 milligrams (mg) injected into a muscle or into a
vein.
-
Children: 1.25 mg per kg (0.6 mg per pound) of body weight four times
a day injected into a muscle.
-
For use as a sedative (to help sleep):
-
For diphenhydramine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults: 50 milligrams (mg) twenty to thirty minutes before bedtime
if needed.
-
For doxylamine
-
For oral
dosage form (tablets):
-
Adults: 25 milligrams (mg) thirty minutes before bedtime if needed.
-
Children: Use and dose must be determined by your doctor.
-
For hydroxyzine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults: 50 to 100 milligrams (mg).
-
Children: 0.6 mg per kg (0.3 mg per pound) of body weight.
-
For injection
dosage form:
-
Adults: 50 milligrams (mg) injected into a muscle.
-
For anxiety:
-
For hydroxyzine
-
For oral
dosage forms (capsules, tablets,
or liquid):
-
Adults: 50 to 100 milligrams (mg).
-
Children: 0.6 mg per kilogram (0.3 mg per pound) of body weight.
-
For injection
dosage form:
-
Adults: 50 to 100 milligrams (mg) injected into a muscle every four
to six hours as needed.
-
Children: 1 mg per kilogram (0.45 mg per pound) of body weight injected
into a muscle.
Missed dose - If you are taking this medicine regularly and you
miss a dose, take it as soon as possible. However, if it is almost time for
your next dose, skip the missed dose and go back to your regular dosing schedule.
Do not double doses. For patients taking this medicine by mouth:
-
Antihistamines can be taken with food or a glass of water or milk
to lessen stomach irritation if necessary.
-
If you are taking the extended-release tablet form of this medicine,
swallow the tablets whole. Do not break, crush, or chew before swallowing.
For patients taking dimenhydrinate or diphenhydramine
for motion sickness:
-
Take this medicine at least 30 minutes or, even better, 1 to 2 hours
before you begin to travel.
For patients using the suppository form of this medicine:
-
To insert suppository: First remove the foil wrapper and moisten
the suppository with cold water. Lie down on your side and use your finger
to push the suppository well up into the rectum. If the suppository is too
soft to insert, chill the suppository in the refrigerator for 30 minutes or
run cold water over it before removing the foil wrapper.
For patients using the injection form of this medicine
:
-
If you will be giving yourself the injections, make sure you understand
exactly how to give them. If you have any questions about this, check with
your health care professional.
Storage - To store this medicine:
-
Keep out of the reach of children, since overdose may be very dangerous
in children.
-
Store away from heat and direct light.
-
Do not store the capsule or tablet form of this medicine in the bathroom
medicine cabinet, near the kitchen sink, or in other damp places. Heat or
moisture may cause the medicine to break down.
-
Keep the liquid form of this medicine from freezing.
-
Do not keep outdated medicine or medicine no longer needed. Be sure
that any discarded medicine is out of the reach of children.
|