You should not use Zyrtec-D if you have narrow-angle glaucoma, severe high blood pressure (hypertension), severe coronary artery disease, if you are unable to urinate, or if you are allergic to hydroxyzine (Atarax, Vistaril). Do not use this medicine if you have taken an MAO inhibitor in the past 14 days.
Zyrtec may interact with other medicines that make you sleepy (such as other cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety).
First generation antihistamines, while very effective at controlling symptoms, are often associated with symptoms in older adults such as anxiety, confusion, sedation, blurred vision, reduced mental alertness, urinary retention and constipation.
Which allergy medications are best for people with high blood pressure? Second-generation antihistamines that are not combined with decongestants are the best choice for people with hypertension. These include oral medications like: Cetirizine (Zyrtec)
Antihistamines are generally viewed as safe, even for people with heart disease or high blood pressure. However, the FDA does state that antihistamines could elevate heart rate and blood pressure temporarily.
"They can raise the blood pressure and increase the pulse, neither of which is ideal in either problem," he says. "They can also increase the risk for heart rhythm disturbances such as atrial fibrillation."
The drowsiness and fatigue which may occur in a small percentage of patients may be more of a problem for the elderly because of the increased risk of bone fracture if they fall. Other medical problems common in elderly patients may contribute to sedation.
So what can older adults safely take for allergy relief? Wozniak: Newer antihistamines such as Claritin® (loratadine) and Allegra® (fexofenadine) tend to be safer and better tolerated.
ZYRTEC-D® Allergy Relief Tablets with Decongestant and Cetirizine HCl. Adults under 65 and children 12 years and older One 10 mg capsule once daily; do not take more than one 10 mg capsule in 24 hours. Adults 65 years and over Ask a doctor. Adults with liver or kidney disease Ask a doctor.
Claritin and Zyrtec are effective and safe for most people with minor allergies. However, as with all medications, there may be some side effects. Loratadine—present in Claritin—may not be safe for people with severe liver conditions.
What's the best time of day to take ZYRTEC®? Any time of day works. And ZYRTEC® will continue to work for 24 hours.
Try to leave 10 to 12 hours between doses. So, one first thing in the morning, and one before bedtime. For children between 2 to 5 years of age, the dose is 2.5mg, twice a day.
Zyrtec is safe for most people, but there are some individuals who should stay away. Children under 2, anyone with a history of an allergic reaction to Zyrtec or hydroxyzine/piperazine derivatives, and those with severe renal impairment shouldn't take Zyrtec, says Dr. Patel.
Antihistamines
Antihistamines are known to cause extreme drowsiness; however, in certain people, they can cause insomnia, excitability, anxiety, restlessness, and a rapid heart rate.
Common ones are stinging nettle, vitamin C, quercetin, butterbur, bromelain, and probiotics. Some alternative practices—such as acupuncture, nasal irrigation, and exercise—may also help you manage symptoms.
Yes, most people can take antihistamines every day, if they have daily symptoms of their allergies.
Rarely, they can cause acute self-limited liver injury. One study has reported a more serious long-term effect, a 3.5-fold increase in the risk of gliomas, a common type of brain tumor in patients with long-term antihistamine use for allergic conditions.
Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: difficulty urinating, fast/irregular/pounding heartbeat, shaking (tremor), mental/mood changes (such as anxiety, confusion, nervousness, restlessness), weakness.
by Drugs.com
The elimination half-life of Zyrtec is between 8 to 9 hours. It takes approximately 5.5 x elimination half-life for a medicine to be cleared from your system. For Zyrtec this is 5.5 x 9 hours which is about 2 days.