Rumination and Bulimia
At the end of this
lecture, student will be able to
the difference between Regurgitation, Rumination and Bulimia
the pathophysiology of vomiting
is often preceded by nausea and may be accompanied by retching
can be a valuable physiological response to the ingestion of a toxic substance
such as alcohol
is also an unwanted side effect of many clinically used drugs, mainly cancer
chemotherapy, opioids, general anesthetics.
It is important to differentiate vomiting from
Regurgitation, Rumination and Bulimia.
interactions between central and peripheral pathways.
most imp areas involved peripherally are the gastric mucosa and smooth muscle
(the enteric brain) and the afferent pathways of the vagus and sympathetic
significant areas involved centrally are the area postrema, the Chemo receptor
Trigger zone (CTZ), the nucleus tractus solitarus (NTS) and the vomiting
pharmacotherapeutic point of view, the most imp aspect of this complex
pathophysiology is the variety of receptors involved including:
In the clinical
situation, this becomes target for various drugs directed at controlling the
most commonly used emetics are Ipecac and Apomorphine.
emesis is the preferred means of emptying the stomach in awake patients who
have ingested a toxic substance or have recently taken a drug overdose.
• Vomiting blood is often caused by
ulcers, ruptured blood vessels, and stomach bleeding. It can also be caused by
some forms of cancer
should not be induced if patient has CNS depression or has ingested certain
volatile hydrocarbons or caustic substances
• Frequent vomiting not related to any
of these causes may be a symptom of cyclic vomiting syndrome.
• This condition is characterized by
vomiting for up to 10 days.
• It is usually coupled with nausea
and extreme lack of energy. It mainly occurs during childhood
syrup(15-30 ml in adults, 10-15 ml in children, 5 ml in infants) is
prepared from the dried rhizome and roots of Cephaelis ipecacuanha or Cephaelis
acuminata, plants from Brazil and Central America
– stimulates the CTZ in the medulla & acts directly on the gastric mucosa –
take w/ water (not milk or carbonation)
in 15 to 30 min.
if absorbed à
• S/E: Hypotension, tachycardia, chest pain
,diarrhea, sedation, lethargy
alkaloid emetine as active principal ingredient
directly on CTZ and indirectly by irritating gastric mucosa
• The chemoreceptor trigger zone at
the base of the fourth ventricle has numerous dopamine receptors
• Serotonin 5-HT3 receptors,opioid
receptors acetylcholine receptors and receptors for substance P
• Stimulation of different receptors
are involved in different pathways leading to emesis, in the final common
pathway substance P appears involved
is cardio toxic if absorbed and causes cardiac conduction disturbances, atrial
fibrilation, or fatal myocarditis
emesis does not occur, gastric lavage using a nasogastric tube must be
• Dehydration is the most common
complication related to vomiting. Vomiting causes your stomach to expel not
only food but fluids
should be available in every household for emergency use.
dependable than parenteral apomorphine
15 min or more for its effect, but is safer
• The vagal and enteric nervous
system inputs transmit information regarding the state of
the gastrointestinal system.
• Irritation of the GI mucosa by
chemotherapy, radiation, distention, or acute infectious gastroenteritis activates
the 5-HT3 receptors of these inputs.
a derivative of morphine, acts as dopaminergic agonist directly on CTZ.
i.m./s.c. In a dose of 6 mg, induces
vomiting within 5 min.
use not recommended as emetic dose is larger.
• The CNS mediates vomiting
that arises from psychiatric disorders and stress from higher brain centers
effective if water is first administered before oral or s.c. dosing.
dosage may cause respiratory depression and circulatory collapse.
antagonists (naloxone) usually reverse the depressant actions of apomorphine.
frequently used as emetic.
• Vomiting is a complex reflex
• Emetic drug or vomiting drug are
those drug which is responsible for the vomiting.
• Emetic drug is apply when an
undesirable like poison has been injected.
an individual has consumed certain toxic substances and must be expelled before