Uropharmacology: VIII. Sympathomimetic agents

Effects of selegiline, phenylpropanolamine, or a combination of both on physiologic and behavioral variables in healthy dogs

OBJECTIVE

To determine effects of selegiline hydrochloride, phenylpropanolamine (PPA), or a combination of both on physiologic and behavioral variables in dogs.

ANIMALS

40 adult hound-type dogs.

PROCEDURE

Dogs were assigned to 4 groups. One group received selegiline (1 mg/kg, PO, q 24 h) and PPA (1.1 mg/kg, PO, q 8 h), a second group received selegiline alone, a third group received PPA alone, and a fourth group received neither drug. Dogs were observed 3 times/d throughout the 30-day study (daily during the first week, on alternate days during the next 2 weeks, and again daily during the final week). Observers recorded rectal temperature, pulse, respiratory rate, oscillometric blood pressure, and lead-II ECG and assessed 4 behaviors, using an analogue scale. Variables were compared among treatment groups by use of a 2-factor ANOVA with data categorized into three 10-day treatment periods. A similar comparison was made among treatment groups with data categorized by time of observation (morning, afternoon, or evening) for all study days.

RESULTS

Variables did not differ among groups at study initiation. Pulse rate was the only variable that differed significantly among treatment groups during the study. During the first 10 days of treatment, dogs receiving PPA had a lower pulse rate than dogs that did not. Although signs of illness were apparent in a few dogs, illness did not appear to be related to treatment.

CONCLUSIONS AND CLINICAL RELEVANCE

Adverse effects were not detected after administration of selegiline, PPA, or a combination of the drugs in healthy dogs.

Intravesical therapy for the treatment of neurogenic bladder in children

BACKGROUND

Oral pharmacotherapy has been commonly used as an adjunct to clean intermittent catheterization (CIC) in the treatment of neurogenic bladder in order to achieve continence, but may be associated with unacceptable side effects. The authors' experience with sterile intravesical preparations of oxybutynin hydrochloride and ephedrine in children is reported here.

METHODS

Patients requiring CIC for neurogenic bladder but with incontinence that was unresponsive to standard oral therapy or that was associated with severe systemic side effects were studied over a 1-year period. Clinical, radiological and urodynamic assessments were made prior to commencing treatment with intravesical oxybutynin hydrochloride. Patients who remained incontinent with poor internal sphincter muscle tone had intravesical ephedrine added.

RESULTS

Seven patients were involved in the study over a 1-year period. Two patients became continent and one patient had an improvement in upper tract dilatation. One patient had a limited improvement with oxybutynin alone but became continent with the addition of ephedrine. Three patients had no response to treatment. There were few side effects.

CONCLUSION

Intravesical agents have a role in the management of paediatric neurogenic bladder for those children with significant adverse sequelae from oral pharmacotherapy who would otherwise require surgical intervention. Intravesical therapy is a safe technique in children with sterile preparations. Further investigation of this modality should be pursued.

Drug-induced illness in the elderly

The elderly are predisposed to adverse drug reactions because of age-related physiologic changes, interaction of one drug with another, and interaction between a drug and a coexisting medical condition. Recognition of such adverse reactions is essential, because many are reversible and many are even preventable. Assessment of clinical disorders in the elderly should include evaluation of drugs as a causal or aggravating factor. Careful choice and dosage of drugs in the elderly will minimize the likelihood of drug-induced illness.

Pharmacological characteristics of smooth muscle in benign prostatic hyperplasia and normal prostatic tissue

Strips of prostatic hyperplastic adenoma and normal prostate were studied by observing the mechanical response to application of certain drugs. The sensitivity of BPH tissue to potassium chloride, phenylephrine and prostaglandins was about double that of normal prostate. The small hyperplastic adenoma showed a higher sensitivity to phenylephrine than the large. However, sensitivity to phenylephrine was almost the same among the various histological types of BPH.