The first line of gastroparesis management includes restoration of fluids and electrolytes, nutritional support and in case of diabetic’s optimization of glycemic control.
Dietary management of gastroparesis
Patients should receive frequent (four to six times a day) small-volume nutrient meals that are low in fat and soluble fiber. If the patient is unable to tolerate solid food, then use of homogenized or liquid nutrient meals. Gastroparesis diagnosis test provides the length and severity of gastric delay, which helps the physician to recommend nutrition, medication, and surgical therapies.
People with diabetes gastroparesis should stop taking Pramlintide and GLP-1 analogs that may delay gastric emptying and use of alternative approaches before initiation of gastroparesis therapy.
Once dietary management of gastroparesis does not produce expected results, then you may need medication to treat delayed gastric emptying. There are different classes of medication available for gastroparesis, they are:
- Antiemetic medication is useful for treating nausea and vomiting. Antiemetic drugs available are dopamine receptor antagonists, Serotonin (5-HT3) receptor antagonists, Antihistamines.
- Prokinetic - can improve gastric emptying and gastroparesis symptoms. Some of the prokinetics that are in use for gastroparesis treatment are metoclopramide and domperidone. Erythromycin does exert prokinetic effect does improve gastric emptying.
- Psychotropic medications - such as antidepressants can help get relief from nausea, vomiting, and reduce pain. Tricyclic antidepressant’s amitriptyline, nortriptyline and desipramine are frequently in use for treatment of gastroparesis.
These are the medications act on peripheral and central neural structures providing support for the treatment of many conditions with nausea and vomiting. Antiemetic drugs may serve as primary therapy for gastroparesis or as an adjunct medication to promote gastric emptying. Phenothiazines are dopamine receptor antagonists, commonly used agents are prochlorperazine, trimethobenzamide, and promethazine. These are available as tablet, liquid suspension, suppository, or injection. Unfortunately, side effects are common they include sedation and extrapyramidal effects. Parenteral prochlorperazine due to several reports of associated tissue necrosis uses it cautiously. This agent provides relief from nausea and vomiting; however, no improvement in gastric emptying.
Serotonin (5-HT3) receptor antagonists, is a newer generation antiemetic that includes ondansetron, granisetron, and dolasetron, are useful for chemotherapy-induced nausea and vomiting. Additionally, it improves symptoms occurring postoperatively or during radiation therapy. If you consider using this class of drugs, best in an as-needed basis. Give it as four mg doses once per day or less, this anticholinergic agent may delay gastric emptying.
Antihistamine’s drug includes diphenhydramine, dimenhydrinate, and meclizine, which acting on H1 receptors exhibit central antiemetic effects. These agents are best effective for nausea secondary to motion sickness.
Scopolamine is a muscarinic antagonist provides relief from nausea and vomiting. It is available both as a transdermal patch and as an oral formulation (Scopace). Dosage is from 0.4 mg to 0.8 mg as needed take up to four times a day. Place the transdermal patch of 1.5 mg behind the ear, and replace it every three days. Scopolamine’s side effects may include drowsiness, fatigue, and blurred vision.
Prokinetic agent increases antral contractility, correct gastric dysrhythmias, improves antroduodenal coordination and promotes small bowel and colon transit. Thus, it improves mobility of entire digestive tract and additionally, improves absorption of nutrients. Consider using prokinetic drugs as oral, intravenous, and sublingual preparations to improve gastric emptying and gastroparesis symptoms, after take into account its benefits and risks of treatment. Preferably, take this medication 30 minutes before meals to get the maximize benefit. Some prokinetics drugs include metoclopramide and domperidone; it also exhibits antiemetic properties. Include bedtime doses to facilitate nocturnal gastric emptying of indigestible solids.
Metoclopramide is the first line of prokinetic therapy administers at the lowest dose possible in a liquid formation for effective absorption. You should stop taking this medication if you develop side effects, including involuntary movements. This drug exhibits both prokinetic and antiemetic actions. It helps prevent postoperative and chemotherapy-induced nausea and vomiting. The usual starting dose of metoclopramide in adults is 10 mg 30 minutes before meals and at bedtime. You can increase the dosage to 20 mg three to four times a day, if the response to 10 mg is inadequate.
The common side effects are:\
- Facial spasm, oculogyric crisis, trismus, and torticollis occur in 0.2 to 6% of patients.
- Drowsiness, fatigue, and lassitude happen in 10% people.
- Up to half of the patients may report somnolence while on metoclopramide.
- Parkinson-like symptoms, depression, and prolactin-related events can occur in anywhere from 1%–15%.
- Tardive dyskinesia is the most feared risk reported in less than 1%, consists of difficult to treat the face, tongue, or extremities involuntary movements.
- It may aggravate underlying depression.
- Other side effects are breast engorgement, lactation, and menstrual abnormalities.
Domperidone: The effects of domperidone on the upper gut are similar to those of metoclopramide, including stimulation of antral contractions and promotion of antroduodenal coordination. For those who are unable to use metoclopramide, domperidone can help them without causing central nervous system side effects. It provides symptom relief and improvement in quality of life with different causes of gastroparesis. Dosage begins at 10mg before meals and at bedtime, and can increase as needed up to 30 mg before meals and every evening or bedtime. The most common side effects are hyperprolactinemia, breast enlargement, galactorrhea, and irregular menses noted in less than 10%. It does not cross the blood-brain barrier; thus much less likely to cause extrapyramidal side effects than metoclopramide. Dosing begins at 10 mg before meals and at bedtime and can increase as tolerated to achieve symptom control.
Erythromycin and motilides: The erythromycin exerts prokinetic effects; it improves gastric emptying and symptoms from delayed stomach emptying. The long-term effectiveness of oral therapy is limiting by tachyphylaxis (a sudden decrease in the response to a drug). Clinically, erythromycin has shown to stimulate gastric emptying in diabetic gastroparesis, idiopathic gastroparesis, and post-operative gastroparesis. Oral erythromycin should initiate at a low dose (125 to 250 mg three or four times a daily). Many prefer to use erythromycin liquid suspension, because it is rapidly absorbed. At higher dosage, erythromycin side effects are nausea, vomiting, and abdominal pain. These symptoms mimic gastroparesis and thus narrowing its application in some patients. It is also considering as adjuvant medications to domperidone and metoclopramide. The intravenous dosage is from two to three mg/kg every six to eight hours. The oral dosing is from 125 mg to 250 mg three times daily before meals and should be given as a suspension to facilitate improved emptying and absorption in gastroparesis. Potentially life-threatening arrhythmia has limited its usage.
Antidepressants can also in use for gastroparesis treatment, to get relief from nausea, vomiting, and to reduce pain.
Tricyclic antidepressants are effective in relieving depression as well as a variety of chronic pain syndromes, nausea, vomiting and abdominal pain. Thus, it may be of use among the gastroparesis patients. Additionally, it may stimulate appetite, weight gain, and promotes sleep. The problematic side effects of tricyclic antidepressants are orthostatic hypotension, palpitations and intra-cardiac conduction slowing. The most widely used drugs are amitriptyline, nortriptyline and desipramine.
General dosage of tricyclic antidepressants is lower than used to treat depression. A reasonable starting dose is 10 to 25 mg at bedtime. The dosage can increase by 10 to 25 mg increments up to 50 to 100 mg titrated up over several weeks. You can consider this drug for refractory nausea and vomiting in gastroparesis but will not result in improved gastric emptying and potentially retard it. Anticholinergic and sedative side effects may limit the maximum dosage achieved, and 25 % patients require a change in medication.
If you have last 10% or more of your body weight within three to six months and/or frequent hospitalization for refractory symptoms, then you need to take enteral nutrition or tube feeding (special liquid food mixture containing protein, carbohydrates (sugar), fats, vitamins and minerals, is given through a tube to the stomach or small bowel).
Gastrojejunostomy or Jejunostomy tube
Patients with severe delayed gastric emptying despite dietary changes may need feeding tubes such as gastrojejunostomy or jejunostomy tubes.
In refractory patients with severe nausea and vomiting, gastrojejunostomy has preferred. A gastrojejunostomy is a surgical procedure connecting the stomach to the second section of the small intestine.
For patients who are unable to maintain nutrition with oral intake, placement of a feeding jejunostomy is useful. Predict the therapeutic response to jejunostomy infusion by a trial of nasojejunal feedings. A jejunostomy is a surgical procedure in which your doctor makes a hole in the small intestine to insert a feeding tube that bypass the stomach entirely. Start nutrient feedings at low infusion rates of 20 mL/h with diluted nutrient meals and advanced slowly (increase of 10 mL/h every 12 hours) until the required daily nutritional intake is reached.
Patients with total gastric emptying failure may not tolerate feeding tubes and require intravenous nutrition.
Gastric pacer therapy
Gastric pacer therapy provides electrical stimulation with a frequency of 10% higher than that of the natural slow wave and paces gastric myoelectric activity with high energy, long duration pulses.
More recently, an implantable neuro-stimulator delivering a high frequency (12 cycles per minute), low energy signal with short pulses has studied in patients with gastroparesis. The stimulating wires are installing into the gastric muscle along the greater curvature during laparoscopy or laparotomy. These wires are connecting to the electric stimulator positioned in a subcutaneous abdominal pouch.