Nausea & Vomiting FINAL

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Nausea is an uneasy or unsettled feeling in the stomach

together with an urge to vomit. Nausea and vomiting, or

throwing up, are

not diseases



can be symptoms

of many different conditions.

These include :

morning sickness during pregnancy, infections,

migraine headaches, motion sickness,

food poisoning,

cancer chemotherapy or other medicines. others



Nausea and vomiting are common. Usually, they are

not serious.

BUT IF the following cases occur immediate

referral is recommended

Vomited for longer than 24 hours

Blood in the vomit

Severe abdominal pain

Headache and stiff neck



Nausea and vomiting consist of three stages:

1. Nausea, : nausea is the subjective feeling of a need to vomit. It is often accompanied by autonomic symptoms such as pallor, tachycardia,

diaphoresis, and salivation

2. Retching, which follows nausea, consists of diaphragm, abdominal wall, and chest wall contractions and spasmodic breathing against a closed glottis. Retching can occur without vomiting, but this stage produces the pressure gradient needed for vomiting, although no gastric contents are expelled.

3. Vomiting, or emesis, is a reflexive, rapid, and forceful oral expulsion of upper gastrointestinal contents due to powerful and sustained contractions in the abdominal and thoracic musculature.1 Vomiting, like nausea, can be

accompanied by autonomic symptoms.

note :

Regurgitation, unlike vomiting, is a passive process without involvement of the abdominal wall and diaphragm wherein gastric or esophageal contents move into the mouth. in patients with gastro esophageal reflux disease (GERD), one

hallmark symptom is acid regurgitation.



Various areas in the brain and the

gastrointestinal (GI) tract are stimulated

when the body is exposed to noxious

stimuli (e.g., toxins), gastro-intestinal

irritants (e.g., infectious agents), or


These areas include :

 the chemoreceptor trigger zone (CTZ) in the

area postrema of the fourth ventricle of the brain,(

outside BBB


serotonin type 3

(5-HT3), neurokinin-1 (NK1), and

dopamine (D2) receptors.

the vestibular system (H1,M)

visceral afferents from the GI tract (5-HT3 R ), the cerebral cortex.



Chemoreceptor trigger zone (CTZ) (5-ht3, D2, NK!)

Gastrointestinal visceral


(5ht3, D2, NK1)

Cerebral cortex

(sensory input )

Vestibular system

(H1, Muscarinic)





Stimulation of

salivation &



pharyngeal ,

GI, Abdominal



Nausea &


Physiologic pathways that result in nausea and vomiting. 5-HT3, serotonin type 3 receptor; D2, dopamine type 2 receptor; GI, gastrointestinal; H1, histamine type 1 receptor, NK1, neurokinin-1. (Adapted from American Society of Health-System Pharmacists. ASHP therapeutic guidelines on the pharmacologic management of nausea and vomiting in adult and pediatric patients receiving

chemotherapy or radiation therapy or undergoing surgery








Motion sickness is caused by stimulation of the vestibular system. This area contains many histaminic (H1) and muscarinic cholinergic


The higher brain (i.e., cerebral cortex) is affected by sensory input

such as sights, smells, or emotions that can lead to vomiting. This area is involved in anticipatory nausea and vomiting associated with


Nausea and vomiting can be classified as either simple or complex. Simple nausea and vomiting occurs occasionally and is either

self-limiting or relieved by minimal therapy. It does not have detrimental effects on hydration status, electrolyte balance, or weight because it is short-lived.

complex nausea and vomiting requires more aggressive therapy because

electrolyte imbalances, dehydration, and weight loss may occur. Unlike simple nausea and vomiting, complex nausea and vomiting can be

caused by exposure to noxious agents.


Rubenstein ED, et al Cancer J 2006



Emetic center

Chemoreceptor trigger zone

Vagal afferents of GI


Dopamine (DA)

Serotonin (5HT)

Substance P


Cannabinoid I



Emetic Center



Assessment & Interpretation


Nature & severity

Projectile vomiting


babies pyloric stenosis ,

Adults with history of peptic ulceration

(usually duodenal ).

Sour smelling vomit

possible obstruction

(e.g. pyloric stenosis)

Blood stained vomit


Blood may appear:

 fresh & bright red, or dark with clotted appearance  If blood originates in the stomach , it will be

degraded by gastric acid producing a dark colored vomit with a coffee ground appearance


Frequent vomiting for more than 24-



nausea ,


incidence of vomiting

over a longer

period of time

Sudden vomiting without nausea

is a

characteristic of a central cause (e.g.

Cerebral tumor or injury),

Nausea preceding vomiting

indicates a

gastrointestinal cause.



Accompanying symptoms

Abdominal pain

may cause

reflex vomiting

as in:

paroxysmal coughing

can lead to vomiting .

Other disorders may lead to vomiting include


disease & acute pain in extra abdominal body system




Diarrhea accompanying vomiting

suggests ,

usually due to ingestion of some dietary insult or

to infection or food

food poisoning :

Recent travelers to hot countries should

be referred to eliminate dysentery &


─ liver disease

─ appendicitis ,

─ biliary colic


Central nervous disorder (e.g. space occupying

lesions, meningitis , head injury & subdural hemorrhage )




or an emotional disturbance

anorexia nervosa & bulimia



Episodic or chronic vomiting accompanied by weight loss

requires referral for investigation of the cause .



If the cause can be elicited, the decision of whether to refer or not becomes easier

 Common dietary cause are hot or spicy foods , over indulgence of food or

alcohol , & sensitivity to certain foods (e.g.. Sea food , pork…). such case will usually resolve spontaneous within 24 hrs.

 Many drugs can cause nausea & vomiting (e.g. NSAIDS, colchicine , digoxin in

toxic doses, Fe , levodopa , theophylline , estrogens & cytotoxic drugs )

Motion is a common cause of N&V, & in severe cases may persist for a day or

2 after the journey

Infection may cause vomiting , especially otitis media in children & the early

stages of various viral illness(measles). Condition affecting the abdomen may result in reflex vomiting.

Heart failure , particularly right sided HF may result in congestion of the

abdominal organs with blood , giving a sensation of nausea & sometimes vomiting.



Episodes of vomiting which may sometimes be severe, in

patients with diabetes , require immediate referral to exclude

loss of

control of the diabetes




patients may suffer from early morning


2 types of vomiting may occur in pregnancy :

 The familiar syndrome of morning sickness comprises regular bouts of

short lived N or V or both during the 1st few weeks of pregnancy. it may

occur at any time of the day . It usually resolve spontaneously around the 3rd month of pregnancy . Drugs should not be recommended but reassurance , frequent small meals , rest , and bed rest in the morning are sensible recommendation .

 A more sever form of vomiting which may occur in early pregnancy Is

hyperemesis gravidarum , it may lead to dehydration & shock & requires medical referral



Risk factors in children

Vomiting in children is usually self remitting but

certain points should be remembered

Many babies regurgitate their milk after meal

(posseting) & mothers should be assured that

this is normal

However , in cases of projectile vomiting (baby

may be alert & appear normal OR in babies who

appear distressed, irritable or very

drowsy)referral is required

Children over 2 years of age require referral if

they have vomited for more than 24hrs


If the cause of vomiting has been identified or is

suspected, the underlying disorder should be

attended to as a priority

Management :

Non pharmacologic





Non pharmacologic management

General Measures:

 resting the stomach

 avoid strong perfumes

 evaporation of mint may be helpful

 sit in an upright position for 30 - 45 minutes after eating

 Avoiding drinking milk or eating heavy or fatty warm, very spicy and

odorous meals for 24 hrs.

 Sips of tasteless drinks, ideally water, should be taken regularly to

prevent dehydration

 Food should be avoided until the patients feels hungry (start with bread

toast or plain biscuits )

 If tolerated , intake may be increased carefully till a normal diet is


 Administration of fluids and electrolytes


Acupuncture and acupressure

There are indications that acupuncture and/or

acupressure (in the form of pressure massage or a special wristband) are effective in the case of nausea and vomiting, particularly after surgery and after chemotherapy.

Complementary therapies and psychological


for psychogenic factors (anxiety and stress) and conditioning (anticipatory nausea and vomiting) play an important role.

These types of nausea and vomiting respond poorly to antiemetics.

These techniques act through relaxation, distraction, and/or a feeling of self-control.


Non pharmacologic management

P6 (Neiguan) point


Pharmacologic drug treatment

There are few oral drugs available to treat vomiting attacks

Both antihistamines & anti muscarinic drugs may be useful

to prevent attacks , especially of motion sickness.

Anti histamine such as cinnarizine , diphenhydramine &

promethazine which also possess anticholinergic properties

, may be useful , but should be used in caution in patients

with glaucoma , prostatitis , constipation & those who



Babies and young children should be given oral rehydration

fluid that replace glucose , Na , K lost during vomiting . Glucose enhance the absorption of electrolytes across the inflamed mucosa .

The use of proprietary rehydration fluids in children should be

encourage over home remedies to prevent inappropriate load of Na , & K


Drug Class Information


 magnesium hydroxide, aluminum hydroxide, and/or calcium carbonate,

relieve N&V, (through gastric acid neutralization.)

Histamine-2 Receptor Antagonists

 cimetidine, famotidine, nizatidine, ranitidine N&V associated with

heartburn or GERD .

Antihistamine–Anticholinergic Drugs

 treatment of simple symptomatology.

 Adverse reactions that may be apparent with the use of the antihistaminic–

anticholinergic agents primarily include drowsiness or confusion, blurred vision, dry mouth, urinary retention, and possibly tachycardia, particularly in elderly patients.

Phenothiazines “ chlorpromazine , promethazine ”

Phenothiazine are most useful in patients with simple nausea and


 dangerous side effects, including extrapyramidal reactions, hypersensitivity

reactions with possible liver dysfunction, marrow aplasia, and excessive sedation.



Metoclopramide increases lower esophageal sphincter tone, aids gastric

emptying, and accelerates transit through the small bowel, possibly through the release of acetylcholine.

 Metoclopramide is used for its antiemetic properties in patients with

diabetic gastroparesis and with dexamethasone for prophylaxis of delayed nausea and vomiting associated with chemotherapy administration.


Dexamethasone has been used successfully in the management of

chemotherapy- induced nausea and vomiting (CINV) and postoperative nausea and vomiting (PONV), either as a single agent or in combination with selective serotonin reuptake inhibitors (SSRIs). For CINV,

dexamethasone is effective in the prevention of both Cisplatin-induced acute emesis and when used alone or in combination for the prevention of delayed nausea and vomiting associated with CINV.


Selective Serotonin Receptor Inhibitors (Ondansetron, Granisetron, Dolasetron, and Palonosetron)

SSRIs (dolasetron, granisetron, ondansetron, and palonosetron) act by blocking

presynaptic serotonin receptors on sensory vagal fibers in the gut wall.

 The most common side effects associated with these agents are constipation, headache,

and asthenia


When compared with conventional antiemetics, oral nabilone and oral dronabinol were

slightly more effective than active comparators in patients receiving moderately emetogenic chemotherapy regimens.

 The efficacy of cannabinoids as compared to SSRIs for CINV has not been studied. They

should be considered for the treatment of refractory nausea and vomiting in patients receiving chemotherapy.

Substance P/Neurokinin 1 Receptor Antagonists

 Substance P is a peptide neurotransmitter in the NK family whose preferred receptor is the

NK1 receptor. Substance P is believed to be the primary mediator of the delayed phase of CINV and one of two mediators of the acute phase of CINV.

Aprepitant is the first approved member of this class of drugs and is indicated as part of a

multiple drug regimen for prophylaxis of nausea and vomiting associated with high-dose cisplatin-based chemotherapy.

 Numerous potential drug interactions are possible; clinically significant drug interactions

with oral contraceptives, warfarin, and oral dexamethasone have been described.





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