Treatment should always be started at a dose of 1.5 mg twice daily and titrated to the patient's maintenance dose. If treatment is interrupted for longer than three days, treatment should be re-initiated with the lowest daily dose to reduce the possibility of adverse reactions (e.g. severe vomiting) (see Dosage & Administration).
Gastrointestinal disorders such as nausea, vomiting and diarrhoea may occur when initiating treatment and/or increasing the dose. They may respond to a dose reduction. In other cases, use of Exelon has been discontinued. Patients who show signs or symptoms of dehydration resulting from prolonged vomiting or diarrhoea can be managed with iv fluids and dose reduction or discontinuation if recognized and treated promptly. Dehydration can be associated with serious outcomes (see Adverse Reactions).
Patients with Alzheimer's disease may lose weight whilst taking cholinesterase inhibitors, including rivastigmine. The patient's weight should be monitored during therapy with Exelon.
Patients with body weight below 50 kg may experience more adverse events and may be more likely to discontinue due to adverse events.
As with other cholinomimetics, care must be taken when using Exelon in patients with sick sinus syndrome or conduction defects (sino-atrial block, atrio-ventricular block) (see Adverse Reactions).
Cholinergic stimulation may cause increased gastric acid secretion and may exacerbate urinary obstruction and seizures. Caution is recommended in treating patients predisposed to such conditions.
Like other cholinomimetics, Exelon should be used with caution in patients with a history of asthma or obstructive pulmonary disease.
Like other cholinomimetics, rivastigmine may induce or exacerbate extrapyramidal symptoms. In patients with dementia associated with Parkinson's disease who were treated with Exelon capsules, worsening of parkinsonian symptoms, particularly tremor, has been observed (see Adverse Reactions).
Skin Reactions: In patients who develop application site reactions suggestive of allergic contact dermatitis to Exelon Patch and who still require rivastigmine, treatment should be switched to oral rivastigmine only after negative allergy testing and under close medical supervision. It is possible that some patients sensitized to rivastigmine by exposure to rivastigmine patch may not be able to take rivastigmine in any form.
Allergic contact dermatitis should be suspected if application site reactions spread beyond the patch size, if there is evidence of a more intense local reaction (e.g. increasing erythema, edema, papules, vesicles) and if symptoms do not significantly improve within 48 hours after patch removal. In these cases, treatment should be discontinued (see Contraindications).
There have been isolated post-marketing reports of patients experiencing allergic dermatitis (disseminated) when administered rivastigmine irrespective of the route of administration (oral, transdermal). In these cases, treatment should be discontinued (see Contraindications). Patients and caregivers should be instructed accordingly.
Special Population: Patients with clinically significant renal or hepatic impairment may experience more adverse reactions. Dosing recommendations to titrate according to individual tolerability should be closely followed (see Dosage & Administration). Patients with severe hepatic impairment have not been studied, however, Exelon capsules may be used in this patient population provided close monitoring is exercised.
Driving and using machines: Alzheimer's and Parkinson's disease dementia may cause gradual impairment of driving performance or compromise the ability to use machinery. Rivastigmine may induce dizziness and somnolence, mainly when initiating treatment or increasing the dose. Therefore, in patients with dementia treated with Exelon, the ability to continue driving or operating complex machines should be routinely evaluated by the treating physician.