Antihistamines chlorphenamine

NITRATES 1. ANALGESICS-nefopam 2. ANTIARRHYTHMICS -disopyramide, propafenone 3. ANTIDEPRESSANTS-TCAs 4. ANTI EMETICS-cydizine 5. ANTIHISTAMINES -chlorphenamine, cyproheptadine, hydroxyzine 6. ANTIMUSCARINICS -atropine, benzatropine, cydopentolate, dicydover-ine, flavoxate, homat-ropine, hyoscine, orphenadrine, oxybutynin, procyclidine, propantheline, tolterodine, trihexyphenidyl, tropicamide. 7. ANTI-PARKINSON S DRUGS-dopaminergics 8. ANTI-PSYCHOTICS - pheno-thiazines, clozapine, pimozide 9. MUSCLE RELAXANTS-baclofen 1. t risk of antimuscarinic side-effects when isosorbide dinitrate is co-administered with these drugs 2. 1 efficacy of sublingual nitrate tablets... 

PARACETAMOL ANTIHISTAMINES Chlorphenamine, cyproheptadine and hydroxyzine may slow the onset of action of intermittent-dose paracetamol Anticholinergic effects delay gastric emptying and absorption Warn patients that the action of paracetamol may be delayed. This will not be the case when paracetamol is taken regularly... 

The signal characteristic of the second-generation antihistamines is their freedom from sedation (2,16). The relative lack of sedative properties in the second-generation antihistamines has been ascribed to their relative hydrophi-licity. Little is known about intracerebral concentrations of antihistamines and their metabohtes, but positron emission tomography has shown that the first-generation antihistamine chlorphenamine occupied a larger fraction of brain histamine Hi receptors than terfenadine (SEDA-20,164). Differential affinity for, or different actions on, central and peripheral Hi receptors (SEDA-21,171) could also explain variations in sedative effect, but differences in receptor binding have only been shown for loratadine in vitro (45). 

Severe pruritus (itching) in children, particularly at night, can be treated with oral antihistamines chlorphenamine syrup is licensed for use from 1 year, promethazine syrup from 2 years. 

Sedating antihistamines (chlorphenamine, promethazine) can be used for night-time relief of irritable dermatitis. 

It is usual to give a sedating antihistamine, for example chlorphenamine 10 mg by intramuscular or slow intravenous injection, because of the relatively short half-life of epinephrine (adrenaline), and because of the active role of histamine in anaphylaxis. In addition, the inflammatory reaction can be moderated by the administration of a corticosteroid, such as hydrocortisone 200 mg by intramuscular or slow intravenous injection. Corticosteroids may take several hours to act, but can be of some help in so-called biphasic anaphylactic reactions. 

Q4 Antihistamines are effective in managing many of the troublesome symptoms of allergic rhinitis. Histamine is a neurotransmitter and a mediator of type 1 hypersensitivity reactions, such as urticaria and hay fever. There are several types of histamine receptors and these allergic conditions can be treated with Hi receptor antagonists, such as promethazine, chlorphenamine and fexofenadine. First-generation antihistamines, such as promethazine, cause sedation and possess side effects associated with actions on muscarinic receptors. Fexofenadine is a newer drug with a longer duration of action, which does not sedate the patient. 

PROTEASE INHIBITORS ANTIHISTAMINES-ASTEMIZOLE, CHLORPHENAMINE, TERFENADINE Possibly t adverse effects with amprenavir, atazanavir, indinavir, ritonavir (with or without lopinavir), saquinavir and tipranavir Inhibition of CYP3A4-mediated metabolism of astemizole the risk is greatest in patients who are slow CYP2D6 metabolizers because chlorphenamine and terfenadine are also metabolized by this route Avoid co-administration... 

The adrenaline should be accompanied by an Hj-receptor antihistamine [say chlorpheniramine (chlorphenamine) 10-20 mg by slow i.v. injection] and hydrocortisone (100-300 mg i.m. or i.v). The adrenal steroid may act by reducing vascular permeability and by suppressing... 

In a comparison of diphenhydramine, chlorphenamine, cetirizine, loratadine, and placebo in 15 healthy elderly subjects, there were no significant differences between the first- and second-generation antihistamines (62). In another study, even the first-generation sedative drug chlorphenamine failed to cause significant sedation in a group of children (63). 

Blood dyscrasias are infrequent with antihistamines, but agranulocytosis, hemolytic anemia, and thrombocytopenia have been described. Thrombocytopenia has been attributed to antazoline (85), agranulocytosis to chlor-phenamine (SEDA-16, 162) and mebhydrolin (86), and aplastic anemia to chlorphenamine (87). 

Chlorphenamine (chlorpheniramine) is a first-generation antihistamine, an alkylamine derivative, with sedative and antimuscarinic activity. 

S. sclarea oil was also able to reduce histamine-induced hind paw edema [48] the antiedematous effect increased progressively in time after the administration of the edema-inducing agent and was greater than chlorphenamine, used as antihistaminic reference drug. 

Antihistamines Brompheniramine, Chlorphenamine, Cyproheptadine, Diphenhydramine, Hydroxyzine, Triprolidine... 

Chlorphenamine, an organic amine, is an antihistamine used to prevent some of the symptoms of allergies. Inset A model of chlorphenamine. ( mandygodbehear/ iStockphoto)... 

Chlorphenamine G is an antihistamine used in the treatment of allergic conditions. It can be prepared using the 3-step approach shown below. 

---