Nausea and Vomiting

July 2006

Chapter Contents

Background

Subjective

Objective

Assessment

Plan

Patient Education

References

Background

Nausea with or without vomiting, and occasionally vomiting without nausea, can occur at any stage of HIV infection. Nausea is a common adverse effect of many antiretroviral (ARV) and other medications and often occurs within weeks of starting new medications. In some cases, nausea causes significant discomfort and may interfere with medication adherence. Nausea and vomiting may also be symptoms of a serious complication of ARV therapy, or a sign of an opportunistic infection or neoplasm in patients with late-stage AIDS. Clinicians must identify the cause of nausea and vomiting and institute appropriate treatment.

S: Subjective

The patient complains of nausea with or without vomiting, or vomiting without nausea.

Ascertain the following during the history:

• Duration of symptoms
• Characteristics, timing, and precipitating factors
• Fever
• Hematemesis
• Jaundice
• Abdominal pain
• Lightheadedness, dizziness, vertigo, or orthostatic symptoms
• Polyuria
• Polydipsia
• Headache
• Changes in vision
• Neck stiffness
• Pruritus
• Hepatitis history
• Pancreatitis history
• Toxoplasmosis encephalitis history
• Cytomegalovirus history
• Cryptococcal (or other chronic meningitis) history
• Central nervous system (CNS) lymphoma history
• Renal failure history
• Unprotected sex or missed menses in women
• Medications, new and ongoing
• Nutritional supplements and nonprescription medications
• Alcohol intake, substance use or abuse

O: Objective

Check vital signs, including orthostatic blood pressure and heart rate measurement.

Conduct a thorough physical examination, including evaluation of the following:

• Skin turgor
• Eyes and fundi (retinal abnormalities such as papilledema)
• Oropharynx (dryness of oral mucosa, thrush, ulcerations)
• Neck (stiffness or other signs of meningeal irritation)
• Abdomen (tenderness, distention, masses, organomegaly)
• Pelvis (tenderness, masses)
• Neurologic system (mental status, focal neurologic abnormalities)

Review recent CD4 measurements, if available, to determine the patient's risk for opportunistic illnesses.

A: Assessment

A partial differential diagnosis includes the following conditions:

• Medication effect or reaction
• Drug-drug interactions
• Foodborne illness
• Pancreatitis
• Meningitis
• Pregnancy
• Adrenal insufficiency
• Toxoplasmosis encephalitis (see chapter Toxoplasmosis )
• Uremia
• Diabetic ketoacidosis
• Lactic acidosis due to nucleoside analogues
• Esophagitis (see chapter Esophageal Problems )
• CNS lymphoma
• Hepatitis, infectious or drug related (see chapters Hepatitis B Infection and Hepatitis C Infection )
• Appendicitis
• Pelvic inflammatory disease (see chapter Pelvic Inflammatory Disease )
• Myocardial infarction

P: Plan

Diagnostic Evaluation

Perform laboratory work and other diagnostic studies as suggested by the history, physical examination, and differential diagnosis. Tests may include the following:

• Complete blood count (CBC) with differential
• Blood urea nitrogen (BUN), creatinine, electrolytes
• Glucose
• Amylase and lipase if symptoms of pancreatitis are present
• Liver function tests (LFTs) and hepatitis serologies for possible acute hepatitis
• Blood cultures and other fever workup as needed (see chapter Fever )
• Computed tomography (CT) scan of the brain if neurologic symptoms are present (see chapter Neurologic Symptoms )
• Cortisol and cortrosyn stimulation test if indicated (eg, fatigue, weakness, unexplained abdominal pain, weight loss, orthostasis; usually in late-stage AIDS)
• If odynophagia or dysphagia is present (see chapter Esophageal Problems )
• Electrocardiogram if patient has chest pain or suspicious symptoms
• Lactic acid levels if lactic acidosis is suspected
• Pregnancy test if indicated
• Consult with an HIV expert to determine whether hospitalization or other laboratory tests are needed

Treatment

Once the diagnosis is made, appropriate treatment should be initiated. In seriously ill patients, presumptive treatment may be started while diagnostic test results are pending. See appropriate chapters in Section 6: Disease-Specific Treatment or other relevant guidelines.

In the case of significant adverse effects from ARVs or other medications, use a substitute for the offending medications, if possible (without compromising the efficacy of the treatment regimen). In the case of serious or life-threatening medication toxicities (eg, lactic acidosis or abacavir hypersensitivity reaction), discontinue the offending medication (see chapter Adverse Reactions to HIV Medications ).

After the workup and exclusion of life-threatening illness, symptomatic treatment can be considered. If nausea and vomiting are due to medications that are vital to the patient, and these complications are not life-threatening, antiemetic therapy may be the best treatment. Chronic therapy is not always necessary. Some patients obtain adequate relief by breaking the "nausea cycle" with effective antiemetics for 1-2 days and then establishing meals or snacks with medications. Patients with dehydration may require administration of fluids (oral or intravenous) to relieve nausea. For patients with chronic nausea resulting in weight loss, refer to a nutritionist for assessment and nutritional support.

Symptomatic treatment

Consider the following strategies for symptomatic treatment:

• Ginger capsules have proven effective in clinical trials for the management of pregnancy-related and chemotherapy-related nausea. Foods and beverages containing ginger (eg, tea, cookies, ginger ale, candies) may help provide relief.
• Promethazine (Phenergan) may be given as a 25-mg oral tablet or a 12.5-mg rectal suppository, every 8-12 hours as needed.
• Prochlorperazine (Compazine) may be given as a 5-mg or 10-mg oral tablet, or a 25-mg rectal suppository, every 6-8 hours as needed. Extended-release Spansule, 10 mg every 12 hours or 15 mg every morning, can also be considered.
• Lorazepam (Ativan) may be given as a 0.5 mg oral tablet one half hour before medications for symptoms of anticipatory nausea. Patients with anticipatory nausea develop significant nausea or vomiting when even thinking about medications or reaching for the medications.
• Dronabinol (Marinol) may relieve nausea, especially when nausea is accompanied by a loss of appetite. This remedy is best tolerated by patients who have tolerated inhaled marijuana. The starting dosage is 5 mg 2 or 3 times daily.
• 5-Hydroxytryptamine (5-HT3) receptor antagonists such as dolasetron (Anzemet) 50 mg and 100 mg, granisetron (Kytril) 1 mg, and ondansetron (Zofran) 4-mg, 8-mg, and 24-mg tablets are highly effective in relieving severe nausea and vomiting due to chemotherapy and other causes. However, access to these medications is limited by their cost. Their use should be considered a short-term strategy.

Patient Education

• Nausea and vomiting can have many different causes. Patients should let their health care providers know if they are having these symptoms so that the most likely cause can be determined.
• Patients should stay nourished and well hydrated even if they are having nausea and vomiting. Eating small, frequent meals may be best tolerated, while avoiding dairy products, greasy foods, and high-fat meals.
• Tell patients not to stop taking any of their medications without first discussing it with their health care providers. Many medications must be continued despite nausea.
• Many patients wonder whether they should take their medicines again if they vomit after taking their dose. Generally, the medicines are still in the system unless the pills actually come back up. Patients should call their health care provider if they have any questions.
• Ginger may help to relieve nausea. Ginger can be taken in a variety of ways, including ginger ale, tea, cookies, candies, or ginger capsules. Patients can choose the form of ginger that works best for them.

References

• Sulkowski MS, Chaisson RE. Gastrointestinal and Hepatobiliary Manifestations of HIV Infection. In: Mandell GL, Bennett JR, Dolin R, eds. Principles and Practice of Infectious Diseases, Vol. 1, 5th ed. Philadelphia: Churchill Livingstone; 2000:1426-31.