Abstract:
There is provided a method of treating colonic viscerosensitivity and spasticity induced by a colonic examination chosen from colonic endoscopy and of barium/air contrast colonic radiography and virtual colonoscopy. The method comprises prescribing and/or administering to a patient in need thereof a pharmaceutically effective oral, sub-lingual, nasal or transdermic dose of a non-centrally-acting opioid agonist for a period of at least two days before the colonic examination.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a method for treating colonic viscerosensitivity and spasticity. In particular, the invention relates to the use of therapeutic agents for the treatment of certain colonic reactions, which are induced by the procedure of colonic endoscopy, of barium/air contrast colonic radiography and/or virtual colonoscopy. Such reactions can be, for example, specific typical bowel reactions induced by the said procedures such as the painful viscerosensitivity and spasticity induced by aeric, gaseous or liquid distension. 
       BACKGROUND OF THE INVENTION 
       [0002]    Barium/air contrast colonic radiography (Computerised Tomography (CT) colonography) and virtual colonoscopy are radiographic techniques aiming at imaging the colon for anatomical appearance, endoluminal lesions or mucosal abnormalities. In both procedures, a small, flexible tube is passed few inches into the rectum, and a small balloon is inflated to allow air to be gently pumped into the colon using a hand-held squeeze bulb. Sometimes, an electronic pump is used to deliver carbon dioxide gas into the colon. The purpose of the gas is to distend the colon to eliminate any folds or wrinkles that might obscure polyps or other lesions from the physician&#39;s view. In the case of colonic radiography, barium (a radio-opaque heavy metal) is also pumped in the rectum, and this barium covers the inner-lining of the colon creating a contrast with the intra-abdominal organs. Mucosal and endo-luminal abnormalities can be depicted and diagnostically interpreted by radiologists. 
         [0003]    In the case of Virtual colonoscopy, CT colonography uses CT scanning to obtain an interior view of the colon (the large intestine) that is ordinarily only seen with an endoscope inserted into the rectum. CT imaging uses special x-ray equipment to produce multiple images or pictures of the inside of the body and a computer to join them together in cross-sectional views of the area being studied. The images can then be examined on a computer monitor or printed. 
         [0004]    Colonoscopy is a test that allows physicians to look at the interior lining of the large intestine (rectum and colon) through a thin, flexible viewing instrument called a colonoscope. A colonoscopy helps detect ulcers, erosions, polyps, tumors, and areas of inflammation or bleeding. During a colonoscopy, tissue samples can be collected (biopsies) and abnormal growths can be removed. Colonoscopy can also be sued as a screening test to identify and remove precancerous and cancerous growths in the colon or rectum. 
         [0005]    Before this test, the colon needs to be cleaned out. Colon prep takes 1 to 2 days depending on the preferred prep selected. 
         [0006]    Endoscopical or virtual Colonoscopy is usually a painful procedure. Air distension of the colon wall, stretching of the mesenteric attachment and colonic spastic contractions are usually the causative factors for the pain experienced by the patients. A better tolerability of nociceptive air distension of the colonic wall, and the fewer spastic contractions allow for a reduced time to reach the coecum and successfully complete the colonic examination, for a better patient&#39;s tolerance of the procedure, and for a better acceptance of repeated procedures. 
         [0007]    No specific guidelines exist to regulate the use of analgesic modalities in the performance of virtual colonoscopy, barium/air contrast colonography or endoscopical colonoscopy. 
         [0008]    For endoscopical colonoscopy, it is therefore not surprising to find an impressive list of proposed analgesia and/or sedation modalities that are used in different countries and in different investigation units i.e. hospital-based or out-patient clinic facilities. This list encompasses general anesthesia performed by anesthesiologists, sedo-analgesia performed by anesthesiologists or gastroenterologists, sedo-analgesia performed by a trained nurse. Sedo-analgesia is the most frequently used type of sedation during colonoscopy worldwide. It is usually achieved by combining midazolam with propofol and/or fentanyl or pethidine. 
         [0009]    When these proposed pharmacological modalities are administered, a constant per- and post-procedure patient monitoring is required to avoid risks of cardio-vascular or respiratory complications, thereby generating increased costs in time, specialized personnel and specialized space allocation. These drawbacks led to the evaluation of the risks and benefits of performing endoscopical colonoscopy with or without sedation. (J Clin Gastroenterology 1998, June: 24(4):279-282). In summary it is now well accepted that it is feasible and safe to perform a successful colonoscopy without sedation, and this usually does not undermine the willingness of patients to undergo a similar procedure in the future. 
         [0010]    It would therefore be highly desirable to be provided with a method that would be an alternative to the previously proposed methods. It would therefore be also highly desirable to be provided with a method that would permit to overcome at least some of the prior art drawbacks. 
       SUMMARY OF THE INVENTION 
       [0011]    In accordance with one aspect of the present invention, there is provided a method of treating colonic viscerosensitivity and spasticity induced by a colonic examination chosen from colonic endoscopy and of barium/air contrast colonic radiography and virtual colonoscopy. The method comprises prescribing and/or administering to a patient in need thereof a pharmaceutically effective oral, sub-lingual, nasal or trans-dermic dose of a non-centrally-acting opioid agonist for a period of at least two days before the colonic examination. 
         [0012]    In accordance with another aspect of the present invention there is provided a method of treating colonic viscerosensitivity and spasticity induced by a colonic examination chosen from colonic endoscopy, barium/air contrast colonic radiography and virtual colonoscopy. The method comprises prescribing and/or administering to a patient in need thereof a pharmaceutically effective intravenous infusion of a non-centrally-acting opioid agonist before carrying out the colonic examination. 
         [0013]    In accordance with another aspect of the present invention there is provided a method for carrying out a colonic examination chosen from colonic endoscopy, barium/air contrast colonic radiography and a virtual colonoscopy on a patient comprising: 
         [0014]    prescribing and/or administering to the patient a non-centrally-acting opioid agonist to be taken at least once a day for at least two days before carrying out the colonic examination so as to eliminate or reduce the risks of pain generated by colonic viscerosensitivity and spasticity induced during the colonic examination; and 
         [0015]    introducing into the patient&#39;s rectum an endoscope, colonoscope or any instrument required for the colonic examination. 
         [0016]    In accordance with another aspect of the present invention there is provided in a method of carrying out a colonic examination chosen from colonic endoscopy, barium/air contrast colonic radiography and a virtual colonoscopy on a patient, the improvement wherein a non-centrally-acting opioid agonist to be taken at least once a day for at least two days before carrying out the colonic examination is prescribed and/or administered to the patient so as to eliminate or reduce the risks of pain generated by colonic viscerosensitivity and spasticity induced during the colonic examination. 
         [0017]    In accordance with another aspect of the present invention there is provided a method for eliminating or reducing the risks of pain generated by colonic viscerosensitivity and spasticity induced during a colonic examination. The method comprises administering a non-centrally-acting opioid agonist to be taken at least once a day for at least two days before the colonic examination. 
         [0018]    In accordance with another aspect of the present invention there is provided the use of a non-centrally-acting opioid agonist for treating viscerosensitivity and spasticity induced during a colonic examination. 
         [0019]    In accordance with another aspect of the present invention there is provided the use of a non-centrally-acting opioid agonist for eliminating or reducing the risks of pain generated by viscerosensitivity and spasticity induced during a colonic examination. 
         [0020]    In accordance with another aspect of the present invention there is provided the use of a non-centrally-acting opioid agonist in the manufacture of a medicament for eliminating or reducing the risks of pain generated by viscerosensitivity and spasticity induced during a colonic examination. 
         [0021]    In accordance with another aspect of the present invention there is provided the use of a non-centrally-acting opioid agonist in a preventive treatment for eliminating or reducing the risks of pain generated by viscerosensitivity and spasticity induced during a colonic examination. 
         [0022]    For example, the non-centrally-acting opioid agonist can be chosen from Trimebutine maleate, Nor-desmethyl trimebutine, azimadolin, their salts, isomers or enantiomers, and mixtures thereof. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    The present invention will be more readily understood by referring to the following example, which represents in a non-limitative manner preferred embodiments. 
       Example 1 
       [0024]    A 52 year old male financial analyst (HB) was referred for colonic polyps screening in the context of familial incidence of colonic cancer; his father had died of metastatic colonic cancer at the age of 62 years. The patient had received a complete colonoscopy three years before in a hospital-based gastrointestinal unit, and this experience left him very anxious concerning the need for a repeat examination. The occurrence of pain during the procedure as well as the discomfort lasting few hours following the colonoscopic examination, despite parenteral sedation/analgesia, was still vivid in his memories. He wanted to negotiate an alternate diagnostic procedure such as a air-contrast barium enema. Because full endoscopical examination of the colon is recognised superior to barium-enema colonography and even to “virtual colonoscopy”, he was proposed and finally accepted a new experimental pharmacological preparation consisting in the administration of Trimebutine maleate 200 mg tablets to be taken orally three times a day for three days before the scheduled examination. He was instructed to completed this pharmacological preparation by taking two Fleet® Phospho-soda 45 ml vials with five or six glasses of liquid one in the evening before the examination, and one in the morning two hours before the examination to clean—prep the colon. He presented alone to the out-patient endoscopy clinic and he was appropriately positioned on his left side on the examination table, and the video-endoscopic colonoscopy was initiated by the endoscopist. The colonoscopy was easily completed to the coecum in 14 minutes. No colonic spastic contractions occurred, and the air-distension of the colon needed for the progression of the instrument did not generate pain or discomfort to the patient. The whole colonic examination including the accurate examination of the colon upon retraction of the instrument lasted a total of 25 minutes and was negative for mucosal lesions nor for endoluminal polypoid formations. The patient then dressed up and walked to the endoscopist&#39;s office to receive the good results of the examination. He was asked several questions on his experience of the new pharmacological preparation as compared to his previous hospital-based unit experience with parenteral sedation/analgesia. He qualified the experience a very positive one; he said he did not experience any pain and very mild discomfort during the procedure. He admitted to be prepared to receive a repeat procedure with the same preparation in a similar set-up, and was happy drive home by himself without any assistance or recovery time. The endoscopist and the assistant nurse were very satisfied with the ease and shortness of the completed procedure. 
       Example 2 
       [0025]    A 62 year old female retired nurse (LA) presented with lower, and occasionally generalised, abdominal cramping together with predominantly loose motions. As part of a complete investigation, a colonoscopy was planned. She was prescribed Trimebutine maleate 200 mg tablets to be taken orally three times a day for three days before the scheduled examination. She was instructed to completed the pharmacological preparation by taking two Fleet® Phospho-soda 45 ml vials with five or six glasses of liquid, one in the evening before the examination, and one in the morning two hours before the examination to clean—prep the colon. Although she presented to the out-patient endoscopy unit with doubts that she could sustain the planned examination without any other drug preparation, having seen in her career many patients undergoing and barely tolerating this procedure of full colonoscopy, even after having received meperidine and/midazolam intravenously before the examination. She also remembered the “stress” striking the endoscopist and the assistant nurse working at completing the examination rapidly and successfully reaching the coecum in these patients. Nonetheless, she consented at trying to receive the examination without further pharmacological preparation, with the promise by the physician that the procedure would be interrupted at her request in the case that she could not tolerate the pain or discomfort. After appropriately positioning the patient on her left side, the instrument was delicately introduced in her rectum, and the progression of the instrument gently initiated. She asked to have her head elevated with a pillow so she could see the video monitor and watch the video-endoscopic recording of her examination. The progression of the instrument in the patient was easy, painless and the coecum was reached in 12 minutes. No spastic contractions delayed the progression of the instrument, and only mild but perfectly tolerable discomfort was experienced by the patient during the examination. The physician and the nurse were surprised by the fact that such a patient presenting a clinical Irritable bowel syndrome could experience so little discomfort during the examination since these patients characteristically are chronically suffering from a very low threshold of viscerosentivity with solid or gaseous distension of the colon. After the procedure, she commented that she would accept to a repeat examination any time, and would not hesitate to recommend this pharmacological preparation to patients needing complete colonoscopy, and would be ready to reassure them that there were no more reasons to fear to receive such examination. 
       Clinical Trial 
     Patients and Method 
       [0026]    A clinical study was then initiated in patients referred by general practitioners to an out-patient endoscopy unit mainly to receive a screening colonoscopy in cases with family history of adeno-carcinoma of the colon. All patients gave informed consent to take part in the trial, which was conducted in accordance with the Revised Declaration of Helsinki. 
         [0027]    Exclusion criteria were:
       i pregnancy or lactation;   ii significant clinical or laboratory evidence of pulmonary, hepatic or renal disease or dysfunction;   iii need for non-steroidal anti-inflammatory drugs, pain-killer drugs or antispasmodic agents.       
 
         [0031]    The study was an open-label, single-institution, unblinded prospective pilot trial aimed at establishing whether a controlled double-blind trial is warranted. 
       Medication 
       [0032]    Trimebutine maleate was used in the form of 200 mg tablets, given three times a day before meals for two or five days before the procedure and for one or two days after the examination 
       Symptom Assessment 
       [0033]    The severity of symptoms experienced during the examination was assessed by the use of a visual analog scale filled in by the patients only a few minutes after the examination, and a telephone call by the assistant nurse was made two days after the procedure to inquire about any symptom or any event having occurred after the patient had resumed its normal activities. The analog scale consisted of a line marked by numbers at equal intervals from 0 to 10. Zero indicated absence of symptoms while 10 represented symptoms severe enough to interrupt the progression of the endoscopic instrument. Assessed symptoms included abdominal pain/discomfort, abdominal distension and flatulence. Symptom scores were tabulated and statistical were analysis carried out using Students t-test. 
         [0034]    This study is in progress and aims at recruiting approximately 50 patients. The results of this study are so far quite encouraging and reflect the results obtained in the individual case studies. 
         [0035]    While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as follows in the scope of the appended claims.