Lab_four__Nausea_and_Vomiting[1].pp powerx
- 1. Nausea and Vomiting Dr. Hawrin Burhan M.Sc. Toxicology
- 2. Introduction • Vomiting: (known medically as emesis) Is the forceful expulsion of the contents of stomach through the mouth and sometimes the nose. • Nausea: The feeling that one is about to vomit is called nausea, which often precedes, but does not always lead to vomiting. • Signs of N/V: Pallor skin, increase respiratory rate, salivation, excessive sweating, abdominal pain, loss of appetite
- 3. Causes of vomiting Vomiting can be caused by a wide variety of conditions: • Gastritis: Gastric stasis, Appendicitis, Pancreatitis. • Neurological: Brain tumors, Meningitis, Middle ear disorders, Headache, • Psychological: anxiety, anorexia, stress. • Medications: alcohol, opioids, antidepressant, anesthesia. • Motion sickness • Pregnancy: morning sickness • Surgery • Poisoning
- 4. Antiemetic drugs • Are group of drugs used in vomiting due to different causes. Classification: • 1. Antimuscarinic, anticholinergic drugs: Hyoscine • 2. Antihistamanic drugs: Cyclizine, Dimenhydrinate. Promethazine. • 3. Dopamine receptors antagonists: Metocloperamide, Domperidone, Prochloperazine. • 4. 5HT3 receptors antagonists: Ondansteron. • 5. Neurokinin receptor (NK1) antagonists: Aprepitant • 6. Other agents: Corticosteroids, Cannabinoids.
- 5. Treatment of nausea and vomiting • 1- Post operatives nausea and vomiting: • Postoperative nausea and vomiting frequently occur in the first 24 hours after anesthesia and surgery. All the following agents are effective for preventing postoperative vomiting. Dexamethasone 8mg Prochlorperazine 12.5mg, Hyoscine Cyclizine 50mg Ondansteron 4mg
- 6. 2- Chemotherapy induced nausea &vomiting • Highly emetogenic chemotherapy Ondasetron 8 mg Dexamethasone 8 mg Plasil 10mg.
- 7. 3-Pregnancy induced nausea & vomiting • Morning sickness: refers to nausea and vomiting that can actually occur during the first month of pregnancy and continues until the 14th to 16th week. • The exact cause of morning sickness is unknown: but It may be caused by hormonal changes Lower blood sugar during early pregnancy. Emotional stress, traveling or some foods can aggravate the problem.
- 8. Drug treatment for morning sickness: • Nausea in the first trimester of pregnancy is generally mild and does not require drug therapy. • For moderate to sever symptoms, Pyridoxine-Doxylamine, Promethazine, Prochlorperazine and Metoclopramide are beneficial. • Doxylamine–Pyridoxine is recommended as a first-line treatment for nausea and vomiting during pregnancy and it is commonly prescribed. • Thiamine must be considered in order to reduce the risk of Wernicke’s encephalopathy.
- 9. 4-Migraine induced nausea & vomiting • Nausea & vomiting in migraine are commonly associated with gastric stasis. • Dopamine antagonist. • Metoclopramide and Domperidone promoting gastric emptying and normal peristalsis. • In severe cases Prochlorperazine supp. is effective. • Antiemetics may be given by IM injection or rectally if vomiting is a problem.
- 10. 5-Motion sickness • Motion sickness is the nausea, disorientation and fatigue that can be induced by head motion. • Histaminergic & muscarinic pathways are involved. Treatment of Motion sickness; • 1. Behavioral Strategies for Motion Sickness • In a car, sit in the front seat. • It is helpful to simply close eyes, or if possible, take a nap. • A simple method for relieving common and mild car sickness is chewing. • Fresh, cool air can also relieve motion sickness
- 11. 2. Medication for Motion Sickness: • Antiemetics agents need to be taken at least 30 minutes before exposure to the activity that can cause the problem. • Anticholinergic and Antihistaminic drug are equally effective. Dimenhydrinate. Cyclizine: used for short trips (e.g. automobile). Promethazine: most effective for motion sickness. Scopolamine patches: these patches are sometimes very helpful. Zofran: serotonin-family anti-nausea drugs, do not prevent motion sickness but they may prevent emesis.
- 12. • Metoclopramide (Plasil®) oral 10mg, ampule, syrup. Uses: N/V associated with gastrointestinal diseases, cytotoxic, migraine. Side effects: • 1. Extra-pyramidal side effect • 2. Diarrhea • 3. Stimulation of prolactin release • Ondansetron: (Zofran®), tab 4mg, 8mg, ampule. Used: Ondansetron is highly effective against N/V induced by cytotoxic drugs and radiotherapy. Side effect: Constipation, Headache and Facial flushing.
- 13. • Domperidone: (Motilium®), oral 10 mg, syrup. Used: For the treatment of N/V associated with gastrointestinal disorders and cytotoxic induced vomiting. Side effect: Gynaecomastia, Galactorrhoea. •Hyoscine: (Buscopan®) tab 10 mg, syrup, ampule. Used: In motion sickness and gastrointestinal disorders Side effect: It mainly causes antimuscarinic adverse effects
- 14. Any question?