Drug Therapy with Atropine Sulfate for the Treatment of Sialorrhea

Sialorrhea, or excessive drooling, is a problem for a considerable number of persons with cerebral palsy, intellectual disability, and other neurological conditions.(1) Unable to manage their oral secretions, affected persons are at increased risk of aspiration, skin maceration, and infection. Care may be compromised since the frequent suctioning and cleaning required to maintain proper hygiene can become very burdensome. Drooling also impedes social integration. Isolation is unfortunately common as saliva soils furniture, carpets, toys, and the clothing of peers, siblings, parents, and caregivers.(2) This article reviews the use of atropine sulfate to reduce salivation and help relieve the medical and social problems of drooling.

Saliva is produced by both the major and minor salivary glands. There are three pairs of major salivary glands: the parotid, submandibular, and sublingual glands. These glands produce approximately 1.5 liters of saliva daily: 70% is from the submandibular glands, 25% is from the parotid glands, and 5% is from the sublingual glands. Minor salivary glands located on the palate, buccal mucosa, and tongue also produce modest amounts of saliva.(3)

The secretory innervation of the salivary glands is primarily under the control of the parasympathetic nervous system.(4) Stimulation of the parasympathetic system causes profuse secretion of watery saliva.(5) Some persons are unable to swallow their saliva fast enough to prevent drooling. Excessive drooling is a distressing condition that can create significant hygienic and psychosocial problems.

Several factors predispose the development of sialorrhea. Incompetent control of orofacial, head, and neck musculature is common in patients with cerebral palsy cerebrovascular accidents, head injuries, mental retardation, motor neuron diseases, Parkinson's disease, and other neurologic disorders. Nasal obstruction with mouth breathing, improper head posture, and severe dental malocclusion may also contribute to sialorrhea.(6) Adverse drug reactions involving tranquilizers, anticonvulsants, and anticholinesterases can aggravate sialorrhea by causing hypersecretion of saliva.(7)

Thorough dental and medical evaluations are important to determine the causes of sialorrhea. Is it because of increased production of saliva; inability to control mouth, lips, or throat muscles; physical abnormalities that impede the transport of saliva, or mental functioning below that required to learn to swallow?(8) Detailed evaluations can help answer this question. Counting the number of bibs or shirts soiled each day provides a subjective estimate of the severity of the condition. Physical findings such as skin maceration on the neck, chest, and hands due to dampness and constant wiping confirm initial impressions of severity and indicate the need for treatment. Saltopine Helps control droolings.

The goal of treatment is to reduce drooling but maintain a moist, healthy oral cavity. To completely eliminate drooling risks the significant complication of xerostomia.(9) Available therapies include the use of anticholinergic drugs, speech therapy, prosthetic devices, behavioral therapy, biofeedback, radiation therapy, and a variety of surgical procedures. No single therapy has been documented to resolve sialorrhea satisfactorily in all patients. Rather, a combination of therapies that includes surgery is often required.(10)

The anticholinergic drug, atropine sulfate, has been shown to reduce by more than 50% of base line levels the amount of resting secretion, intraoral accumulation, and pharyngeal-laryngeal pooling of saliva.(11) The drug is a competitive antagonist of the muscarinic actions of acetylcholine. It does not prevent the release of acetylcholine but antagonizes the effect of this neurotransmitter on the effector cells. This action results in drying of the mouth through reduction of salivary gland secretions.(12) Atropine-induced inhibition of salivation occurs within 30 minutes to one hour. Inhibition peaks within two hours after oral administration but can persist for up to four hours. The usual oral dose for adults is 0.4 mg every 4 to 6 hours. In children, the suggested dose is 0.01 mg/kg, but generally not exceeding 0.4 mg every 4 to 6 hours.(13)

The drug is well absorbed from the small intestine. Following oral administration of a single radiolabeled 2 mg dose in healthy fasting adults, about 90% of the dose was absorbed. Peak plasma concentrations occur within one hour. The plasma half-life for atropine sulfate is about 2.5 hours. The drug is metabolized by the liver and excreted by the kidney.(14) drooling

Salivary secretions are generally inhibited at doses lower than those required to affect other organs.(15,16) Nevertheless, one must be aware of a variety of potential adverse effects. These include vasodilation; drying of the mouth; inhibition of contractions of the gastrointestinal tract, ureter, and bladder; reduction of bronchial, gastric, and sweat gland secretions. In addition, the drug may cause dilation of the pupils (mydriasis); paralysis of accommodation (cycloplegia); and in patients with narrow angle glaucoma, increase intraocular pressure.(17)

Atropine sulfate can also affect the heart by altering its rate. Rate often decreases by about 4 to 8 beats per minute after ingestion of an average clinical dose (0.4 mg). There are no accompanying changes in blood pressure or cardiac output. Larger doses, however, cause progressively increasing tachycardia by blocking vagal effects on the SA nodal pacemaker.(18) drooling

Because of these potential side effects, atropine sulfate is contraindicated in patients with asthma, glaucoma, or synechia (adhesions) between the iris and lens of the eye.(19)

Prudent drug therapy necessitates prescribing the lowest effective dose to minimize the risk of adverse reactions. Atropine sulfate may be perscribed as a component of a comprehensive treatment plan that incorporates several specialties. The drug's relatively short half-life adds significant flexibility to the treatment plan. Doses can be customized to reflect the varying needs of each patient at different times throughout the day. Doses may also be titrated easily to respond to gradual changes in disease severity that occur over longer periods of time. Used in this manner, atropine sulfate can be very useful in treatment intended to maintain consistent control of salivation. drooling

In summary, sialorrhea is a frequent problem in persons with neurologic disabilities that impair orofacial control. Serious medical and psychosocial problems may result. Used in combination with other treatment modalities, drug therapy with atropine sulfate may help provide consistent control of salivation to improve hygiene and self-esteem.

References

1. Holtaling, A., et al. Postoperative technetium scanning in patients with submandibular duct diversion. Arch Otolaryngol Head Neck Surg. 1992; 118: 1331-1333.
2. Crysdale, W. and White, A. Submandibular duct relocation for drooling: a 10 year experience with 194 patients. Otolaryngol Head Neck Surg 1989; 101: 87-92.
3. Lew, K., Younis, R., and Lazar, R. The Current Management of Sialorrhea. Ear, Nose and Throat Journal 1991; 70: 99-105.
4. Myer, C. Sialorrhea. Pediatric Clinics of North America 1989; 36: 1495-1500.
5. Lew. Ibid.
6. Lew. Ibid.
7. PDR Drug Interactions and Side Effects Index. Medical Economics Publishing Company. Oradell, New Jersey. 42nd Edition. Page 904.
8. Rapp, D. Drool control: long-term follow-up. Develop. Med. Child Neurol. 1980; 22: 448-453.
9. Morgan, D., et al. Salivary disease in childhood. Ear, Nose and Throat Journal 1989; 68: 155-159.
10. Lew. Ibid.
11. Dworkin, J. and Nadal, J. Nonsurgical treatment of drooling in a patient with closed head injury and severe dysarthria. Dysphagia 1991; 6: 40-49.
12. SAL-TROPINE Prescribing Information. Hope Pharmaceuticals. 1994.
13. AHFS Drug Information 1992. American Hospital Formulary Service. American Society of Hospital Pharmacists. Bethesda, Maryland. Pages 637-659.
14. American Society of Hospital Pharmacists. Ibid.
15. American Society of Hospital Pharmacists. Ibid.
16. Drug Evaluations. American Medical Association. Chicago, Illinois. 1986; 6th Edition: 968-971.
17. Hope Pharmaceuticals. Ibid.
18. Weiner, N. Atropine, scopolamine, and related antimuscarinic drugs. In: The Pharmacological Basis of Therapeutics. Editors: Gilman, A., Goodman, L., Gilman, A. Macmillan Publishing Company. New York, New York. 1980; Sixth Edition: 120-137.
19. Hope Pharmaceuticals. Ibid.

 

DENTISTS:
Maintain a
Dry Field with
Sal-Tropine