Dimetindene-Is the minimum toxic dose for children too strict?

Dimetindene is a sedating antihistamine indicated for the symptomatic treatment of allergic conditions. Dimetindene is marketed among others under the trade name Fenistil (oral solution). Toxicity data are limited, and there is no consensus on the dose at which children require hospitalization. Objective is to determine the potentially toxic dose in children. Data in children with age up to 15 years were obtained from hospital discharge reports. Of 139 paediatric hospital discharge reports, 23 cases (16.5%) were excluded because of uncertain ingestion. In 116 children (46 boys and 70 girls, mean age 2 years and 9 months ± 1 year and 1 month), the majority of children developed no symptoms (87 children, 75%, mean age 3 years±1 year) and the remaining 29 children (25%, mean age 2 years and 11 months ± 1 year and 3 months) developed only mild and spontaneously resolving symptoms of poisoning after a dose of 0.82 ± 0.32 mg/kg b.w. (range 0.26-1.82 mg/kg). In 98% of all cases, hospitalized children were observed for a maximum 24 h, and their condition did not require specific treatment. In conclusion, the prognosis for accidental dimetindene poisoning in children appears to be good and the minimum toxic dose has been determined to be 0.5 mg/kg b.w.

Anti-inflammatory efficacy of topical preparations with 10% hamamelis distillate in a UV erythema test

In 40 volunteers the efficacy of three lotions with 10% hamamelis distillates from different suppliers, two vehicles, dimethindene maleate 0.1% gel, hydrocortisone 1% cream and hydrocortisone 0.25% lotion were investigated in a modified UV erythema test with three UV dosages (1.2, 1.4 and 1.7 MED). The test preparations were applied occlusively over a 48-hour period following irradiation. Chromametric measurement of redness and visual assessment were performed 24, 48 and 72 h after induction of erythema. The hydrocortisone formulations were most effective in erythema suppression. An anti- inflammatory effect was noted for all three hamamelis lotions as well as for the vehicles. A significantly greater suppression of erythema than seen with the vehicles was noted for one of the hamamelis lotions at 1.4 MED. The efficacy of the antihistamine dimethindene maleate did not surpass the hamamelis lotions or the vehicles. Even though the differences between the hamamelis lotions were slight, it was possible to make an objective selection of the best hamamelis distillate for aftersun purposes.

Anti-oedematous action of some H1-receptor antagonists

The oedema disk technique was used to study the effects of orally administered H1-receptor antagonists (cetirizine, chloropyramine, clemastine, cyproheptadine, dimethindene, loratadine, mequitazine and terfenadine) on the inflammation induced with capsaicin or croton oil in the mouse ear, and the effect of topically applied dimethindene maleate gel on the inflammation induced with croton oil in the mouse ear. In rats of the Wistar strain, oedema was induced in the hind paw by the subplantar injection of dextran or compound 48/80. Preliminary antihistamine treatment inhibited the development of oedema in the mouse ear, and of oedema in the rat paw, to statistically significant extents, in a dose-dependent manner. In all experiments, the most potent drugs were loratadine and cyproheptadine.

Dimethpyrindene. Use in high dosage hyposensitization therapy; prevention of constitutional and excessive local reactions

To give larger doses of antigen for hyposensitization, yet hold down constitutional reactions and excessive local reactions, the antigen was mixed with epinephrine, ephedrine and dimethpyrindene, the latter a new antihistamine, just before subcutaneous injection. Dimethpyrindene, a potent antihistamine with minimal side effects, was also administered orally. The incidence of constitutional reactions and excessive local reactions was considerably diminished. Larger doses of antigens were tolerated and longer intervals between treatments were possible, a point of particular significance in maintenance therapy. There was less pain and discomfort at the site of injection and clinical results were improved.