Constipation

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List of terms related to Constipation

Constipation or irregularity, is a condition of the digestive system where a person (or animal) experiences hard feces that are difficult to egest. It may be extremely painful, and in severe cases (fecal impaction) lead to symptoms of bowel obstruction. The term obstipation is used for severe constipation. Causes of constipation may be dietary, hormonal, anatomical, a side effect of medications (e.g. some painkillers), or an illness or disorder. Treatments consist of changes in dietary and exercise habits, the use of laxatives, and other medical interventions depending on the underlying cause.

Signs and symptoms

• 

  Types 1 and 2 on the Bristol Stool Chart indicate constipation

Constipation is one of the most common digestive complaints. It varies greatly between different people, as each person's bowel movements differ. Rate of defecation is not in itself a problem, as infrequent defecation without problems is not abnormal. Constipation is most common in children and older people, and affects women more than men. In children, constipation can lead to soiling (enuresis and encopresis).

In common constipation, the stool is hard and difficult and painful to pass. Usually, there is an infrequent urge to void. Straining to pass stool may cause hemorrhoids and anal fissures, which are themselves painful. In later stages of constipation, the abdomen may become distended and diffusely tender and crampy, occasionally with enhanced bowel sounds.

The definition of constipation includes the following:

• infrequent bowel movements (typically 3 times or less per week)
• difficulty during defecation (straining during more than 25% of bowel movements or a subjective sensation of hard stools), or
• the sensation of incomplete bowel evacuation.

Severe cases ("fecal impaction") may feature symptoms of bowel obstruction (vomiting, very tender abdomen) and "paradoxical diarrhea", where soft stool from the small intestine bypasses the impacted matter in the colon.

Diagnosis

The diagnosis is essentially made from the patient's description of the symptoms. Bowel movements that are difficult to pass, very firm, or made up of small rabbit-like pellets qualify as constipation, even if they occur every day. Other symptoms related to constipation can include bloating, distention, abdominal pain, or a sense of incomplete emptying.

Inquiring about dietary habits may reveal a low intake of dietary fiber or inadequate amounts of fluids. Constipation as a result of poor ambulation or immobility should be considered in the elderly. Constipation may arise as a side effect of medications (especially antidepressants and opiates). Rarely, other symptoms suggestive of hypothyroidism may be elicited.

During physical examination, scybala (manually palpable lumps of stool) may be detected on palpation of the abdomen. Rectal examination gives an impression of the anal sphincter tone and whether the lower rectum contains any feces or not; if so, then suppositories or enemas may be considered. Otherwise, oral medication may be required. Rectal examination also gives information on the consistency of the stool, presence of hemorrhoids, admixture of blood and whether any tumors or abnormalities are present.

X-rays of the abdomen, generally only performed on hospitalized patients or if bowel obstruction is suspected, may reveal impacted fecal matter in the colon, and confirm or rule out other causes of similar symptoms.

Chronic constipation (symptoms present for more than 3 months at least 3 days per month) associated with abdominal discomfort is often diagnosed as irritable bowel syndrome (IBS) when no obvious cause is found. Physicians caring for patients with chronic constipation are advised to rule out obvious causes through normal testing.

Causes

The main causes of constipation include:

• Hardening of the feces
  • Improper mastication (chewing) of food
  • Insufficient intake of dietary fiber
  • Dehydration from any cause or inadequate fluid intake
  • Medication, e.g. diuretics and those containing iron, calcium, aluminium
• Paralysis or slowed transit, where peristaltic action is diminished or absent, so that feces are not moved along
  • Hypothyroidism (slow-acting thyroid gland)
  • Hypokalemia
  • Injured anal sphincter (patulous anus)
  • Medications, such as loperamide, opioids (e.g. codeine & morphine) and certain tricyclic antidepressants
  • Severe illness due to other causes
  • Acute porphyria (a rare inherited condition)
  • Lead poisoning
• Dyschezia (usually the result of suppressing defecation)
• Constriction, where part of the intestine or rectum is narrowed or blocked, not allowing feces to pass
  • Stenosis (Strictures)
  • Diverticula
  • Tumors, either of the bowel or surrounding tissues
  • Retained foreign body or a bezoar
• Psychosomatic constipation, based on anxiety or unfamiliarity with surroundings.
  • Functional constipation
  • Constipation-predominant irritable bowel syndrome, characterized by a combination of constipation and abdominal discomfort and/or pain
• Smoking cessation (tobacco smoking has a laxative effect)
• Abdominal surgery, other types of surgery, childbirth

Complete Differential Diagnosis of the Causes of Constipation

(In alphabetical order)

5-HT3 antagonist 5-Hydroxytryptophan Acamprosate (patient information) Acebutolol (patient information) Actiq Acute Intermittent Porphyria Adhesion Adjustable gastric band Aldesleukin (patient information) Alendronate (patient information) Alfentanil Hydrochloride Injection (patient information) Alfuzosin (patient information) Aluminium hydroxide Amiodarone Oral (patient information) Amitriptyline (patient information) Amobarbital (patient information) Amyloidosis Amyotrophic Lateral Sclerosis Anagrelide (patient information) Anal atresia Anastrozole (patient information) Aprepitant (patient information) Aripiprazole (patient information) Ascites Atorvastatin Atovaquone (patient information) Auranofin Autonomic neuropathy Barium Sulfate (patient information) Batten disease Belladonna Alkaloid Combinations and Phenobarbital (patient information) Benign colonic tumors Benzatropine Benzonatate (patient information) Bepridil (patient information) Berdon syndrome Bezafibrate Bile acid sequestrant Bismuth Subsalicylate, Metronidazole, and Tetracycline Combination (patient information) Blastocystosis Bortezomib (patient information) Botulism Bowel obstruction Buspirone (patient information) Butabarbital (patient information) Calcitriol Calcium carbonate (patient information) Capecitabine (patient information) Carbamazepine (patient information) Carboplatin (patient information) Carteolol (patient information) Celiac disease Cerivastatin (patient information) Cetuximab Injection (patient information) Chagas Disease Chlordiazepoxide (patient information) Chloropyramine Chlorpropamide Cholestyramine Choline Magnesium Trisalicylate (patient information) Chronic amebiasis Cidofovir Injection (patient information) Cimetidine Hydrochloride Injection (patient information) Cimicifuga racemosa Cisapride (patient information) Cladribine (patient information) Clofarabine Injection (patient information) Clomipramine Clonazepam (patient information) Clonidine Clorazepate (patient information) Clozapine Codeine (patient information) Colesevelam (patient information) Colestipol (patient information) Colofac Colonic stricture Colorectal cancer Complications of pregnancy Conn's Syndrome (primary aldosteronism) Cornelia de Lange Syndrome Corrosive enema Crohn's disease Cystic fibrosis Daptomycin Darbepoetin Alfa Injection (patient information) Darifenacin (patient information) Darunavir (patient information) Dehydration Dermatomyositis Descending perineum syndrome Desipramine (patient information) Dextroamphetamine and Amphetamine (patient information) Dextropropoxyphene Diabetes Mellitus Diacetyldihydromorphine Diazepam (patient information) Dicyclomine (patient information) Diethylcathinone Diflunisal Dihydroetorphine Diltiazem (patient information) Diphenhydramine Disopyramide (patient information) Diuretic Diverticular stricture Diverticulosis Dolasetron Mesylate Injection (patient information) Doripenem Dosulepin hydrochloride Doxepin (patient information) Duloxetine Enfuvirtide Injection (patient information) Enteric Neuropathy Eosinophilic colitis Epoetin Alfa Injection (patient information) Esomeprazole (patient information) Estazolam (patient information) Estradiol Topical (patient information) Ethcathinone Ethosuximide Ethylmorphine Etodolac (patient information) Etoposide Extrinsic compression Famotidine (patient information) Felbamate (patient information) Felodipine (patient information) Fenofibrate (patient information) Fenoprofen (patient information) Fentanyl Citrate Injection (patient information)

Ferrous Sulfate (Iron) (patient information) Fludarabine Phosphate (patient information) Fluphenazine (patient information) Flurazepam (patient information) Fluvoxamine Food allergy Food intolerance Fructose malabsorption Fulvestrant Injection (patient information) Furosemide (patient information) Gabapentin (patient information) Ganciclovir (patient information) Gastroptosis Gatifloxacin (patient information) Gemcitabine Hydrochloride (patient information) Gemfibrozil (patient information) Glucagonoma Glycopyrrolate (patient information) Granisetron (patient information) Guanethidine (patient information) Guanfacine H2 antagonist Haloperidol Hashimoto's thyroiditis Hernia Heroin Hexamethonium Hirschsprung's disease Hookworm Hydralazine (patient information) Hydroxyurea (patient information) Hydroxyzine Hyoscyamine (patient information) Hypercalcemia Hypervitaminosis D Hypokalemia Hypothyroidism Hypotonia Ibandronate (patient information) Ileus Imatinib (patient information) Imipramine (patient information) Imperforate anus Indomethacin (patient information) Inflammatory Bowel Syndrome Insulin lispro injection (patient information) Interferon Beta-1b Injection (patient information) Internal intussusception Intestinal pseduoobstruction Intraabdominal/pelvic tumors Intussusception Iron deficiency anemia Iron supplements Irritable bowel syndrome Ischemic colitis Isocarboxazid (patient information) Itraconazole (patient information) Kaolin and Pectin (patient information) Ketogenic diet Ketorolac Lack of fiber Lamivudine and Zidovudine (patient information) Lamotrigine (patient information) Lanthanum (patient information) Lassa fever Lead poisoning Letrozole (patient information) Leuprolide (patient information) Levalbuterol Oral Inhalation (patient information) Levetiracetam (patient information) Levodopa and Carbidopa (patient information) Levomethadyl (patient information) Levorphanol Oral (patient information) Linezolid Lofepramine Lomotil Loperamide Loprazolam Lorazepam (patient information) Lovastatin (patient information) Low fluid intake Low-residue diet Loxapine Oral (patient information) Lymphogranuloma venereum Magaldrate Meclofenamate (patient information) Mefenamic Acid (patient information) Meningocele Meperidine (patient information) Meropenem Injection (patient information) Mesalamine (patient information) Mesoridazine Oral (patient information) Metformin (patient information) Methadone Methsuximide Oral (patient information) Methyprylon Metoclopramide Metoprolol (patient information) Milk-alkali syndrome Misoprostol Modafinil (patient information) MOPP (medicine) Morphine Motofen Multiple endocrine neoplasia (MEN 2b) Multiple Sclerosis Muscular dystrophies Mycophenolate (patient information) Myxedema Myxedema Nabumetone (patient information) Nateglinide oral (patient information) Nefazodone (patient information) Neuroblastoma Nialamide Nicardipine (patient information) Nifedipine (patient information) Nilutamide (patient information) Nimodipine (patient information) Nizatidine (patient information) Nortriptyline (patient information) Olanzapine (patient information) Omeprazole (patient information) Ondansetron Opisthorchis infection Osteitis fibrosa cystica Ovarian cancer Oxaliplatin injection (patient information) Oxazepam (patient information) Oxcarbazepine (patient information) Oxybutynin (patient information)

Oxycodone Pamidronate injection (patient information) Pancrelipase (patient information) Panhypopituitarism Papaverine Paralytic ileus Parkinson's Disease Paroxetine Peginterferon alfa-2b (patient information) Pemetrexed injection (patient information) Pergolide (patient information) Perphenazine oral (patient information) Pethidine Phenelzine (patient information) Phentermine (patient information) Phenytoin oral (patient information) Pheochromocytoma Pholcodine Pimozide (patient information) Piperacillin sodium and tazobactam sodium Piroxicam (patient information) Polio Polyp (medicine) Posaconazole (patient information) Pramipexole (patient information) Prazepam (patient information) Prazosin and polythiazide (patient information) Prednisolone Pregabalin (patient information) Primary hyperparathyroidism Procarbazine (patient information) Procyclidine (patient information) Progressive supranuclear palsy Propafenone (patient information) Propantheline Propoxyphene (patient information) Propranolol Oral (patient information) Protriptyline (patient information) Pseudocyesis Pseudohypoparathyroidism Quetiapine Rabeprazole (patient information) Ranitidine (patient information) Ranolazine (patient information) Rasagiline (patient information) Reboxetine Rectal carcinoma Rectocele Renal cell carcinoma Repaglinide (patient information) Rett syndrome Ribavirin (patient information) Rilmenidine Risperidone (patient information) Rivastigmine (patient information) Ropinirole (patient information) Rosuvastatin (patient information) Sacrococcygeal teratoma Saquinavir (patient information) Scleroderma Scopolamine Secobarbital (patient information) Selegiline (patient information) Sevelamer (patient information) Sibutramine Sibutramine Simethicone Simvastatin (patient information) Sirolimus (patient information) Sitaxsentan Smoking cessation Solifenacin Sorafenib (patient information) Sotalol (patient information) SSRI discontinuation syndrome Stomach cancer Sucralfate Sufentanil citrate injection (patient information) Sulindac (patient information) Sunitinib Suxamethonium chloride Syphilis Tamoxifen (patient information) Tapentadol Temazepam (patient information) Temozolomide (patient information) Terazosin Teriparatide (rDNA origin) Injection (patient information) Thalidomide Thioridazine (patient information) Thiothixene Oral (patient information) Tianeptine Tiludronate (patient information) Tinidazole (patient information) Tiotropium Tolterodine Topiramate Topotecan Hydrochloride (patient information) Toxic megacolon Tranylcypromine (patient information) Travel constipation Triazolam (patient information) Triclofos Trifluoperazine Oral (patient information) Trihexyphenidyl (patient information) Trimethadione (patient information) Trimipramine (patient information) Tropisetron Trospium (patient information) Tuberculosis Typhoid fever Ulcerative colitis Upper gastrointestinal series Valproic Acid (patient information) Venlafaxine Verapamil Vicodin Vigabatrin Viloxazine Vinblastine (patient information) Vincristine Vinorelbine Visceroptosis Volvulus Vorinostat (patient information) Wandering spleen Zaleplon (patient information) Zidovudine Injection (patient information) Zileuton (patient information) Ziprasidone (patient information) Zoledronic Acid Injection (patient information) Zolpidem (patient information) Zonisamide (patient information) Zotepine

Complete Differential Diagnosis of the Causes of Constipation

(By organ system)

Physical Examination

• Complete physical examination including thyroid examination

Abdomen

• Examination of abdomen:

  • Palpate for masses
  • Surgical scars
  • Hernias
  • Hepatosoplenomegaly

    • Examination results are usually normal

Other

• Complete rectal examination with attention paid to:

  • Presence of stool
  • Masses
  • Fistulas
  • Hemorrhoids
  • Abscesses
  • Fissures
  • Squeezing and resting of sphincter tone
  • Palpable relaxation of anal tone and perineal descents

Laboratory Findings

• Complete blood count (CBC)
• Blood urea nitrogen (BUN) / creatinine
• Phosphate
• Glucose
• Liver function tests (LFTs)
• Fecal occult blood test
• Thyroid function tests
• Calcium

Echocardiography or Ultrasound

• Ultrasound may be used to detect tumors, fibroids, ovarian cysts or pregnancy

Other Diagnostic Studies

• Colonoscopy for patients:

  • Greater than 50 years old
  • Present with constipation with no apparent cause
  • Presence of blood in the stool

• Sigmoidoscopy for all other patients
• To rule out ova and parasites, a stool examination should be considered

Treatment

In people without medical problems, the main intervention is to increase the intake of fluids (preferably water) and dietary fiber. The latter may be achieved by consuming more vegetables and fruit and whole meal bread, and by adding linseeds to one's diet. The routine non-medical use of laxatives is to be discouraged as this may result in bowel action becoming dependent upon their use. Enemas can be used to provide a form of mechanical stimulation.

In alternative and traditional medicine, colonic irrigation, enemas, exercise, diet and herbs are used to treat constipation.

Laxatives

Main article: laxative

Laxatives may be necessary in people in whom dietary intervention is not effective or is inappropriate. Most laxatives can be safely used long-term, although some are associated with cramping and bloatedness and can cause the phenomenon of melanosis coli.

Physical intervention

Constipation that resists all the above measures requires physical intervention. Manual disimpaction (the physical removal of impacted stool) is done by patients who have lost control of their bowels secondary to spinal injuries. Manual disimpaction is also used by physicians and nurses to relieve rectal impactions. Finally, manual disimpaction can occasionally be done under sedation or a general anesthetic—this avoids pain and loosens the anal sphincter.

Many of the products are widely available over-the-counter. Enemas and clysters are a remedy occasionally used for hospitalized patients in whom the constipation has proven to be severe, dangerous in other ways, or resistant to laxatives. Sorbitol, glycerin and arachis oil suppositories can be used. Severe cases may require phosphate solutions introduced as enemas.

Prevention

Constipation is usually easier to prevent than to treat. The relief of constipation with osmotic agents, i.e. lactulose, polyethylene glycol (PEG), or magnesium salts, should immediately be followed with prevention using increased fiber (fruits, vegetables, and grains) and a nightly decreasing dose of osmotic laxative. With continuing narcotic use, for instance, nightly doses of osmotic agents can be given indefinitely (without harm) to cause a daily bowel movement.

Recent controlled studies have questioned the role of physical exercise in the prevention and management of chronic constipation, while exercise is often recommended by published materials on the subject.

In various conditions (such as the use of codeine or morphine), combinations of hydrating (e.g. lactulose or glycols), bulk-forming (e.g. psyllium) and stimulant agents may be necessary to prevent constipation.

Epidemiology

Depending on the definition employed, constipation occurs in 2% of the population; it is more common in women, the elderly and children

In animals

Hibernating animals can experience tappens that are usually expelled in the spring. For example, bears eat many foods that create a "rectal plug" before hibernation.

See also

• Diarrhea
• Feces

External links

• Template:MerckHome
• Template:MedlinePlusOverview

Cardiovascular	No underlying causes
Chemical / poisoning	Lead poisoning,
Dermatologic	No underlying causes
Drug Side Effect	5-HT3 antagonist, 5-Hydroxytryptophan, Acamprosate (patient information), Acebutolol (patient information), Actiq, Aldesleukin (patient information), Alendronate (patient information), Alfentanil Hydrochloride Injection (patient information), Alfuzosin (patient information), Aluminium hydroxide, Amiodarone Oral (patient information), Amitriptyline (patient information), Amobarbital (patient information), Anastrozole (patient information), Aprepitant (patient information), Aripiprazole (patient information), Anagrelide (patient information), Atorvastatin, Atovaquone (patient information), Auranofin, Barium Sulfate (patient information), Benzatropine, Benzonatate (patient information), Bepridil (patient information), Bezafibrate, Bile acid sequestrant, Bortezomib (patient information), Buspirone (patient information), Butabarbital (patient information), Calcitriol, Calcium carbonate (patient information), Capecitabine (patient information), Carbamazepine (patient information), Carboplatin (patient information), Carteolol (patient information), Cerivastatin (patient information), Cetuximab Injection (patient information), Chlordiazepoxide (patient information), Chloropyramine, Chlorpropamide, Cholestyramine, Choline Magnesium Trisalicylate (patient information), Cidofovir Injection (patient information), Cimetidine Hydrochloride Injection (patient information), Cisapride (patient information), Cladribine (patient information), Clofarabine Injection (patient information), Clomipramine, Clonazepam (patient information), Clonidine, Clorazepate (patient information), Clozapine, Codeine, Codeine (patient information), Colesevelam (patient information), Colestipol (patient information), Colofac, Daptomycin, Darbepoetin Alfa Injection (patient information), Darifenacin (patient information), Darunavir (patient information), Desipramine (patient information), Dextroamphetamine and Amphetamine (patient information), Dextropropoxyphene, Diacetyldihydromorphine, Diazepam (patient information), Dicyclomine (patient information), Diethylcathinone, Diflunisal, Dihydroetorphine, Diltiazem (patient information), Diphenhydramine, Disopyramide (patient information), Diuretic, Dolasetron Mesylate Injection (patient information), Doripenem, Dosulepin hydrochloride, Doxepin (patient information), Duloxetine, Enfuvirtide Injection (patient information), Epoetin Alfa Injection (patient information), Esomeprazole (patient information), Estazolam (patient information), Estradiol Topical (patient information), Ethcathinone, Ethosuximide, Ethylmorphine, Etodolac (patient information), Etoposide, Famotidine (patient information), Felbamate (patient information), Felodipine (patient information), Fenofibrate (patient information), Fenoprofen (patient information), Fentanyl Citrate Injection (patient information), Ferrous Sulfate (Iron) (patient information), Fludarabine Phosphate (patient information), Fluphenazine (patient information), Flurazepam (patient information), Fluvoxamine, Fulvestrant Injection (patient information), Furosemide (patient information), Gabapentin (patient information), Ganciclovir (patient information), Gatifloxacin (patient information), Gemcitabine Hydrochloride (patient information), Gemfibrozil (patient information), Glycopyrrolate (patient information), Granisetron (patient information), Guanethidine (patient information), Guanfacine, H2 antagonist, Haloperidol, Hexamethonium, Hydralazine (patient information), Hydroxyurea (patient information), Hydroxyzine, Hyoscyamine (patient information), Ibandronate (patient information), Imatinib (patient information), Imipramine (patient information), Indomethacin (patient information), Insulin lispro injection (patient information), Interferon Beta-1b Injection (patient information), Iron supplements, Isocarboxazid (patient information), Itraconazole (patient information), Kaolin and Pectin (patient information), Lamivudine and Zidovudine (patient information), Lamotrigine (patient information), Lanthanum (patient information), Letrozole (patient information), Leuprolide (patient information), Levalbuterol Oral Inhalation (patient information), Levetiracetam (patient information), Levodopa and Carbidopa (patient information), Levomethadyl (patient information), Levorphanol Oral (patient information), Linezolid, Lofepramine, Lomotil, Loperamide, Loprazolam, Lorazepam (patient information), Lovastatin (patient information), Loxapine Oral (patient information), Magaldrate, Meclofenamate (patient information), Mefenamic Acid (patient information), Meropenem Injection (patient information), Mesalamine (patient information), Mesoridazine Oral (patient information), Metformin (patient information), Methadone, Methsuximide Oral (patient information), Methyprylon, Metoclopramide, Metoprolol (patient information), Misoprostol, Modafinil (patient information), MOPP (medicine), Morphine, Motofen, Nabumetone (patient information), Nateglinide oral (patient information), Nefazodone (patient information), Nicardipine (patient information), Nifedipine (patient information), Nilutamide (patient information), Nimodipine (patient information), Nizatidine (patient information), Nortriptyline (patient information), Olanzapine (patient information), Omeprazole (patient information), Ondansetron, Oxaliplatin injection (patient information), Oxazepam (patient information), Oxcarbazepine (patient information), Oxybutynin (patient information), Oxycodone, Pamidronate injection (patient information), Pancrelipase (patient information), Paroxetine, Peginterferon alfa-2b (patient information), Pemetrexed injection (patient information), Pergolide (patient information), Perphenazine oral (patient information), Pethidine, Phenelzine (patient information), Phentermine (patient information), Phenytoin oral (patient information), Pholcodine, Pimozide (patient information), Piperacillin sodium and tazobactam sodium injection (patient information), Piroxicam (patient information), Posaconazole (patient information), Pramipexole (patient information), Prazepam (patient information), Prazosin and polythiazide (patient information), Prednisolone, Pregabalin (patient information), Procarbazine (patient information), Procyclidine (patient information), Propafenone (patient information), Propantheline, Propoxyphene (patient information), Propranolol Oral (patient information), Protriptyline (patient information), Quetiapine, Rabeprazole (patient information), Ranitidine (patient information), Ranolazine (patient information), Rasagiline (patient information), Reboxetine, Repaglinide (patient information), Ribavirin (patient information), Rilmenidine, Risperidone (patient information), Rivastigmine (patient information), Ropinirole (patient information), Rosuvastatin (patient information), Saquinavir (patient information), Scopolamine, Secobarbital (patient information), Selegiline (patient information), Sevelamer (patient information), Sibutramine, Simethicone, Simvastatin (patient information), Sirolimus (patient information), Sitaxsentan, Sorafenib (patient information), Sotalol (patient information), Sucralfate, Sufentanil citrate injection (patient information), Sulindac (patient information), Sunitinib, Suxamethonium chloride, Tamoxifen (patient information), Tapentadol, Temazepam (patient information), Temozolomide (patient information), Terazosin, Teriparatide (rDNA origin) Injection (patient information), Thalidomide, Thioridazine (patient information), Thiothixene Oral (patient information), Tianeptine, Tiludronate (patient information), Tinidazole (patient information), Tiotropium, Tolterodine, Topiramate, Topotecan Hydrochloride (patient information), Tranylcypromine (patient information), Triazolam (patient information), Triclofos, Trifluoperazine Oral (patient information), Trihexyphenidyl (patient information), Trimethadione (patient information), Trimipramine (patient information), Tropisetron, Trospium (patient information), Valproic Acid (patient information), Venlafaxine, Verapamil, Vicodin, Vigabatrin, Viloxazine, Vinblastine (patient information), Vincristine, Vinorelbine, Vorinostat (patient information), Zaleplon (patient information), Zidovudine Injection (patient information), Zileuton (patient information), Ziprasidone (patient information), Zoledronic Acid Injection (patient information), Zolpidem (patient information), Zonisamide (patient information), Zotepine,
Ear Nose Throat	No underlying causes
Endocrine	Conn's Syndrome (primary aldosteronism), Diabetes Mellitus, Glucagonoma, Hypothyroidism, Myxedema, Panhypopituitarism, Pheochromocytoma, Pseudohypoparathyroidism,
Environmental	Change of environment,
Gastroenterologic	Adhesion, Anal atresia, malformation, stenosis, Ascites, Benign colonic tumors, Bowel obstruction, Celiac disease, Crohn's disease, Chronic amebiasis], Colonic stricture, Colorectal Cancer, Corrosive enemas Descending perineum syndrome, Diverticular stricture, Diverticulitis, Extrinsic compression, Eosinophilic colitis, Gastroptosis, Hernia, Hirschsprung's Disease, Ileus, Imperforate anus, Inflammatory Bowel Syndrome, Intraabdominal/pelvic tumors, Intussusception, Irritable Bowel Syndrome, Ischemic colitis, Paralytic ileus, Perianal abscess, Proctitis (ulcerative), Rectal, anal carcinoma, Rectal prolapse, Rectal ulcer, Rectocele, enterocele Ulcerative colitis, Volvulus, Wandering spleen,
Genetic	Hereditary internal anal sphincter myopathy, Batten disease, Cornelia de Lange Syndrome, Cystic fibrosis,
Hematologic	Acute Intermittent Porphyria, Amyloidosis,
Iatrogenic	Postoperative disorder, Adjustable gastric band, Upper gastrointestinal series,
Infectious Disease	Blastocystosis, Botulism, Chagas Disease, Chronic amebiasis, Hookworm, Lassa fever, Lymphogranuloma venereum, Syphilis, Tuberculosis, Typhoid fever, Opisthorchis infection, Polio,
Musculoskeletal / Ortho	Osteitis fibrosa cystica,
Neurologic	Amyloidosis, Amyotrophic Lateral Sclerosis, Autonomic neuropathy, Chagas Disease, Diabetes Mellitus, Hirschsprung's Disease, Intestinal pseduoobstruction, Meningocele, Multiple endocrine neoplasia (MEN 2b), Multiple Sclerosis, Muscular dystrophies, Neurofibromatosis, Paraplegia, Parkinson's Disease, Scleroderma, Spinal lesions, Tabes Dorsalis, Progressive supranuclear palsy,
Nutritional / Metabolic	Food intolerance, Hypercalcemia, [[[Hypokalemia]], Hypervitaminosis D, Iron deficiency anemia, Lack of fiber, Low fluid intake, Low-residue diet, Starvation, Ketogenic diet, Milk-alkali syndrome,
Obstetric/Gynecologic	Endometriosis, Ovarian cancer, Complications of pregnancy,
Oncologic	Colorectal Cancer, [[Benign colonic tumors,]], Multiple endocrine neoplasia (MEN 2b),, Neuroblastoma, Rectal carcinoma, Renal cell carcinoma, Stomach cancer,
Opthalmologic	No underlying causes
Overdose / Toxicity	No underlying causes
Psychiatric	Obsessive/compulsive disorder, Psychosis, Pseudocyesis,
Pulmonary	No underlying causes
Renal / Electrolyte	Uremia,
Rheum / Immune / Allergy	Scleroderma,
Sexual	No underlying causes
Trauma	Spinal cord injury,
Urologic	Urogenital tumors
Miscellaneous	Berdon syndrome, Corrosive enemas, Dehydration, Dietary change’s, Fasting, reduced food intake, Eating disorder, Emotional stress , Extended bed rest, Food allergy, Hypotonia, Idiopathic constipation, Repressed urge to defecate, Rett syndrome, Smoking cessation, SSRI discontinuation syndrome, Travel constipation,