ABSTRACT
The prevalence of annoying hyperhidrosis (HH) in patients with spinal cord traumatic lesions was investigated by a questionnaire. A total of 192 patients were sent the questionnaire, 154 patients answered, and 41 patients reported annoying sweating. Of these 41 patients, 13 had a somatic underlying cause and 28 indicated having annoying HH without a contributing somatic cause. Twenty-five patients with spinal cord injury (SCI) were included in a double-blind, randomized, placebo-controlled, crossover trial using dextropropoxyphene hydrochloride (DP) in a slow release form (Abalgin Retard 150 mg Benzon Pharma A/S, Copenhagen) twice a day, for the treatment of annoying HH. Nineteen patients with lesions between C4 and L4 completed the study. Eight found the active drug to be so effective that they wanted to continue the treatment while 3 preferred placebo. Six patients dropped out, 5 due to adverse effects. There was a trend towards an effect on sweating in daytime (p = 0.08-0.14). Given that the patients had a preference, which 15 of 19 had, the true frequency of patients preferring active treatment ranged from 32 to 84% (95% exact confidence limits). For those with SCI above T6 level the limits ranged from 40 to 97%. We conclude that in spite of the lack of statistically significant effect, it seems worthwhile to try DP for annoying HH, especially in patients with lesions above T6 level.
Subject(s)
Dextropropoxyphene/therapeutic use , Hyperhidrosis/drug therapy , Spinal Cord Injuries/complications , Adult , Aged , Dextropropoxyphene/adverse effects , Double-Blind Method , Female , Humans , Hyperhidrosis/epidemiology , Hyperhidrosis/etiology , Male , Middle Aged , Patient Satisfaction , Prevalence , Treatment OutcomeABSTRACT
Using an in vitro technique it has been demonstrated that water-emulsifying and hydrophobic ointments containing boric acid liberate only minute amounts (1-6%) within 24 h compared with the nearly total liberation from a jelly. When an amount of boric acid containing ointment is swallowed, the absorption is only slightly delayed compared with a similar intake when dissolved in water, and in both cases nearly total excretion is found in the urine within 96 h. The halflife (t 1/2 beta) is 21 h (mean, 7 adult men). The pharmacokinetics rule out the risk of cumulative poisoning with topical preparations containing low amounts of boric acid. The use of water-emulsifying ointments containing up to 3% boric acid should be safe, even for repeated daily use in the napkin region.
Subject(s)
Boric Acids/adverse effects , Boric Acids/metabolism , Humans , KineticsABSTRACT
Boric acid taken orally by six male volunteers in a cross-over study was absorbed to equal extents from a water solution and a 3% waterless, water-emulsifying ointment, though with a slight initial delay in the latter case. Virtually complete gastro-intestinal absorption and renal excretion were indicated by the 96-hr urinary recovery, amounting to 89.1-98.3% (mean 93.9%) and 89.2-97.5% (mean 92.4%) of the dose ingested as solution and ointment, respectively, normal daily boron excretion having been taken into account. The in vitro release of boric acid, measured for 24 hr by dialysis in water at 37 degrees C, reached 95% from a purely water-based jelly but only about 5% from the water-emulsifying ointment. The low boric acid release from the ointment was not significantly influenced when the ointment was dialysed against buffer solutions of pH 2.5 and 9.6 instead of water, or when the maximum possible amount of water (26.9% w/w) was incorporated into the ointment before dialysis. The 24-hr boric acid release from a number of other oil-based ointments, either hydrophobic or water-emulsifying and containing 1-3% boric acid and 0-28.5% water, was also low (0.9-18.3% of the boric acid content). This indicates that the formulation of the ointment is an important factor in determining the extent of release of boric acid when the ointment is applied externally, but that it does not alter the absorption of boric acid should the ointment be ingested.
Subject(s)
Boric Acids/metabolism , Intestinal Absorption , Administration, Oral , Adult , Boric Acids/administration & dosage , Humans , Kidney/metabolism , Male , Middle Aged , Ointments , Solubility , WaterABSTRACT
No rise in the boron content of the plasma of 22 newborn infants was demonstrated following repeated daily application of a water-emulsifying ointment containing the equivalent of 3% boric acid to the napkin region. The mean plasma-boron concentration fell over 5 days from a pretreatment value of 0.49 to 0.29 mg/litre, the corresponding values in ten untreated neonates being 0.62 and 0.21 mg/litre, respectively. No statistically significant differences were found. The results confirm the safety of such ointments for application to the skin, a conclusion predicted by theoretical estimates of the maximum possible boric acid absorption following application of the ointment.
Subject(s)
Boric Acids/metabolism , Boron/blood , Infant, Newborn , Skin Absorption , Boric Acids/administration & dosage , Humans , OintmentsABSTRACT
Three per cent boric acid incorporated in an anhydrous, water-emulsifying ointment causes no increase of boron levels in blood and urine during a period of 1-9 days after a single topical application. The same amount of boric acid incorporated in a water-based jelly does cause an increase in blood and urine levels, beginning within 2-6 h after application. The decisive factor is the degree of liberation of boron from the vehicle. Skin conditions, such as erythema, eczema, or psoriasis are of minor importance to boron skin permeability, as compared to the characteristics of the vehicle. Blood levels and urine excretion of boron depend on the daily uptake of boron through food.
