Pregnancy antihistamines

This compound has antihistaminic activity and is usehil in the therapy of motion sickness. It may also be effective in the control of post-operative nausea and vomiting. It is classified as FDA Category B for Pregnancy, ie, no demonstrated risks shown in animal studies however, no controlled trials in pregnant women. Large doses may cause drowsiness and dry mouth owing to decreased secretion of saUva. 

Amantadine is used cautiously in patients with seizure disorders, psychiatric problems, renal impairment, and cardiac disease. Amantadine is a Pregnancy Category B drug and is used cautiously during pregnancy and lactation. Concurrent use of antihistamines, phenothiazines, tricyclic antidepressants, disopyramide, and quinidine may increase the anticholinergic effects (dry mouth, blurred vision, constipation) of amantadine... 

Intranasal corticosteroids are the most effective treatment for allergic rhinitis during pregnancy. Beclomethasone and budesonide have been used most. Nasal cromolyn and first-generation antihistamines (chlorpheniramine, tripelennamine, and hydroxyzine) are also considered first-line therapy. Loratadine and cetirizine have not been as extensively studied. 

Pregnancy vomiting is prone to occur in the first trimester thus pharmacotherapy would coincide with the period of maximal fetal vulnerability to chemical injury. Accordingly, antiemetics (antihistamines, or neuroleptics if required) should be used only when continuous vomiting threatens to disturb electrolyte and water balance to a degree that places the fetus at risk. 

First-generation antihistamines Flypersensitivity to specific or structurally related antihistamines newborns or premature infants nursing mothers monoamine oxidase (MAO) therapy pregnancy (hydroxyzine) angle-closure glaucoma, stenosing peptic ulcer, symptomatic prostatic hypertrophy, bladder neck obstruction, pyloroduodenal obstruction, elderly, debilitated patients (cyproheptadine). 

As first choice treatment a well-established antihistamine such as meclozine is recommended. Promethazine is another antihistamine which reduces nausea, but sedation is a not always desired adverse effect. Metoclopramide increases intestinal motility and could be used short term also early in pregnancy. A neuroleptic such as prochlorperazine reduces nausea but should only be used for shortterm treatment due to the risk of extrapyramidal adverse reactions. Serotonin receptor antagonists can be used in post-operahve nausea and during treatment with cytostatics. 

Use with alcohol, CNS depressants, antihistamines, opiate analgesics, and other BZDs increases CNS depression. Quazepam is a pregnancy-risk category X drug, and breast-feeding whiie taking it is not recommended. 

Hi antihistamines are contraindicated in cases of known hypersensitivity reactions to individual agents. Oral preparations are also contraindicated in nursing mothers and in the third trimester of pregnancy.The Hi... 

Seto A, Einarson T, Koren G. Pregnancy outcome following first trimester exposure to antihistamines meta-analysis. Am J Perinatol 1997 14(3) 119-24. 

Mazzotta P, Koren G. Nonsedating antihistamines in pregnancy. Can Earn Physician 1997 43 1509-11. 

Example Pseudoephedrine hydrochloride (Actifed, Sudafed), phenylpropanolamine (Allerest, Dimetapp), phenylephrine HCK (Neo-Synephrine, Sinex), and pseudoephedrine (Actifed, Sudafed) frequently combined with an antihistamine, analgesic, or antitussive (anticough) in oral cold remedies Route Tablet, capsule, liquid Pregnancy category C Pharmacokinetic Absorbed by the GI tract, metabolized in liver and excreted in urine. Not removed by hemodialysis... 

Schatz M, Petitti D. Antihistamines and pregnancy. Ann Allergy Asthma Immunol 1997 78 157-159. 

The nausea and vomiting associated with the first trimester of pregnancy are benign and self-limiting in nature. If at all possible, no medications should be used. If absolutely necessary, antihistaminics (meclizine and trimethobenzamide) may be effective. Pyridoxine (vitamin Bg) should not be prescribed, as it may predispose the infant to vitamin Bg-dependent syndrome. 

Besides the specific uses discussed, the general therapeutic uses of antihistaminics include allergic reactions such as urticaria, allergic rhiiutis, motion sickness, vestibular disturbances, and the nausea and vomiting associated with pregnancy. 

Antihistaminics are widely used in the palliative treatment in allergic conditions like hay fever, urticaria, some forms of pruritus, rhinitis, conjunctivitis, nasal discharge, mild asthma etc. A few antihistaminics possess potent antiemetic action and hence are frequently employed in the prevention and treatment of irradiation sickness, motion sickness (air, sea, road), nausea in pregnancy and postoperative vomiting. 

Drug interactions other narcotics, antihistamines, benzodiazepines, antipsychotics, antianxiety agents, or other CNS depressants. Use of MAO inhibitors or tricyclic antidepressants can increase the effect of hydrocodone. It is not recommended for pediatric use Pregnancy Category C [1,2,8]. 

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