constipation

Definition*is adecrease in the frequency of fecal elimenation*hard / dry and somtime painfull stools*normal stool range from three time daily to three time per week

Epidemiology

*age : higher in people more than 65 years*gender : higher in women

causes*insufficient dietary fiber*inadequate fluid intake*lack of exercise*medication: narcotic analgesic / anti cholinergic( anti depresent , anti spasmodic , anti histamine)*pregnancy : the increase size of uterus ,hormonal change ,*organic proplem such tumer or irritable bowel syndrome

Practitioners shuold question patient about

*normal stool frequency*duration of constipation*frequency of constipation episodes*exercise routine*amount of dietary fiber and fluid intake*current medication*medication used to relieve constipation

Treatmentnonpharmacological

*increase intake of fluid and fiber*increase exercise to increase bowel tone

Pharmacological

1: bulk forming laxative : natural or synthetic polysaccharide derivatives that adsorb water to soften the stool and increase bulk which stimulate peristalsis *work on both small and large intestine*onset of action 12-24 and up to 72 hours *best used to prevent constipation rather than treat

Natural bulk forming laxative

1: psylliumAdult 3.5g one to three time dailyChildren: half the adult dose2: malt soup extractAdult 8-16g two to four time daily Children : 16g one to two time daily

Synthetic bulk forming laxative

1: methyl celluloseAdult : 1-2g one to three time dailyChildren : .5g one to three time daily2: polycarbophilAdult : 1g one to four time dailyChildren : .5g one to three time dailyCalcium polycarbophil may impair absorption of tetracyclines

Administration guidelines

*must be given with water*some may contain sugar

Adverse effect

*abdominal cramping and flatulence

2 : saline and osmotic laxatives

*Creat an osmotic gradient to pull water into the small and large intestine , this increase volume and increase peristalsis and bowel motility*increase the activity of cholecystokinin-pancreozyme that increase the secretion of fluid into GI *rectal formulation (enemas,supp) 5-30 onset*oral : 3-6 hour

Salaine laxative

*sodium and magnesium salt*may cause hyper magnesemia *magnesium citrate*magnesium hydroxide*magnesium sulfate*sodium phosphate

Osmotic laxative

A: glycerin : rectal product ( supp.enemas) safe*rectal burning , local irritant effect may occur B : lactulose : only by prescreotion *may cause flatulence and cramping and must take with fruite juice

C : polyetheleneglycol by prescreption *more effective than lactulose and less abd cramp

D : sorbitol : nonabsorbable sugar similar in efficacy to lactulose and can be taken orally or rectally *flatulence , cramping , abd pain are adverse effect

Stimulent laxative

Work on small and large intestine to stimulate bowel motility and increase fluid secretion into the bowel*oral preparation 6-12hr onset of action*rectal preparation 15-60min*should not be used more than one week*abd cramp , fluid def , hypokalemia

A: anthraquinone laxative

*include senna*discoloration of the urine( red, brown)*cascara and casanthranol : carcinogenic*include sennoside :potent and causes cramps

B: bisacodyl

*enteric coated tablet not chewed*not taken with antacids and milk

C: castor oil

2-6 hr onset of action*work primarily on small intestine *cathartic effect may lead to dehydration*not used in pregnant

Emollient laxatives

Act as surfactant by allowing absorption of water into stool*slow onset of action*diarrhea and cramps1: docusate sodium2: docusate calcium3: docusate potassium

Lubricant laxativesmineral oil

Work at the colon to increase water retintion to soften the stool*should be taken in empty stomach•because of possible aspiration of mineral oil into the lung not taken at bed time•May cause anal seepage result in itching

Trade name

laxin glycerin

imlax lactulose

Lax-ray senna

Laxative comp Ipecac + belladona

laxadin bisacodyl

dilax bisacodyl

Glycerine supp glycerin

Konsyl orange psyllium