Hepatotoxicity. Cetirizine and levocetirizine use are not generally associated with liver enzyme elevations, but have been linked to rare instances of clinically apparent liver injury.
Cetirizine (applies to Zyrtec) renal/liver disease
Cetirizine is eliminated primarily by the kidney but also undergoes metabolism in the liver to some extent. Patients with renal and/or liver disease may be at greater risk for adverse effects from cetirizine due to decreased drug clearance.
Cetirizine is unlikely to do you any harm if you take it for a long time. However it's best to take cetirizine only for as long as you need to. If you take it regularly over a long period there's a very small chance of severe itching if you stop treatment suddenly.
The nonsedating antihistamines, however, are often used for an extended period and several forms have been linked to rare instances of clinically apparent acute liver injury which has generally been mild and self-limiting; the antihistamines most commonly linked to liver injury have been cyproheptadine, cetirizine and ...
Cetirizine and levocetirizine use are not generally associated with liver enzyme elevations, but have been linked to rare instances of clinically apparent liver injury.
Diphenhydramine is a first generation antihistamine that is used for symptoms of allergic rhinitis and the common cold. It is also commonly used as a mild sleeping aid. Diphenhydramine has not been linked to instances of clinically apparent acute liver injury.
Dr Grant confirms that many people can suffer withdrawal symptoms if they stop taking antihistamines suddenly. Dr Grant recommends the patient resume taking the antihistamines and then slowly reduce the dose to wean off slowly.
Allergists recommend long-acting, non-sedating antihistamines — ones that won't make you sleepy — for everyday use. Though you may know them by their brand names, the generic versions tackle the same problems: Cetirizine (Zyrtec®, Aller-Tec®, Wall-Zyr®).
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.
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.
Drowsiness, tiredness, and dry mouth may occur. Stomach pain may also occur, especially in children. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Loratadine—present in Claritin—may not be safe for people with severe liver conditions. The liver has to break down loratadine. The kidneys break down cetirizine—found in Zyrtec—and the body excretes it in the urine, largely unchanged. Claritin is more likely to interact with other drugs than Zyrtec.
Acetaminophen. Taking acetaminophen in excess is the leading cause of drug-induced liver injury.
Loratadine, cetrizine, and fexofenadine all have excellent safety records. Their cardiovascular safety has been demonstrated in drug-interaction studies, elevated-dose studies, and clinical trials. These three antihistamines have also been shown safe in special populations, including pediatric and elderly patients.
It's generally safe to take the newer generation of antihistamines daily if you have year-round allergy symptoms. But make sure to avoid anything that has a "D" in its brand name, which stands for decongestants. Long-term use of decongestants will worsen your allergy symptoms.
There are some potential side effects and there are some cases where long-term antihistamine use can worsen urinary retention or narrow angle glaucoma.
When antihistamines block histamine, our appetite can increase. This, plus side effects like drowsiness, could lead to weight gain. Your risk of gaining weight from antihistamines may depend on many factors. But a healthy diet, physical activity, and other lifestyle factors can help you manage your risk.
Some people report that if they stop such antihistamines suddenly, they can experience levocetirizine (Xyzal) and cetirizine (Zyrtec) withdrawal itching.
"Itching can occur within one-two days of stopping Zyrtec or Xyzal after long term daily use (months to years). It usually lasts a few days and then resolves. The intensity of the itching can be from mild to severe. Occasionally, a brief burst of oral steroids may be needed to help the patient get off the drug.
Acetaminophen (Tylenol)
It works by blocking specific chemical reactions in the body that cause pain and inflammation. Compared with other over-the-counter pain relievers, acetaminophen is less toxic to the liver and also tends to have fewer major side effects in other organ systems.
Histamine Stimulates Liver OEA Biosynthesis via H1 Receptor Activation To further test this idea, we examined whether pharmacological blockade of histamine receptors affects liver OEA formation. His- tamine activates with submicromolar potencies four G protein- coupled receptors, termed H1 to H4 (Bongers et al., 2010).
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.