AHS 307 - Gastrointestinal Drugs

Proton pump inhibitors are medications that work by blocking the pumping action of the H+ pump in the lining of the gastric mucosa. This pump is responsible for producing stomach acid, and by inhibiting its action, proton pump inhibitors reduce the production of acid in the stomach. This helps to alleviate symptoms of conditions such as gastroesophageal reflux disease (GERD) and peptic ulcers, as excessive stomach acid can contribute to these conditions. By blocking the pumping action of the H+ pump, proton pump inhibitors effectively reduce the amount of acid produced in the stomach, leading to symptom relief.

Omeprazole (Prilosec/Gastrogard) is a medication that inhibits the proton pump, which is responsible for producing stomach acid. It achieves this by binding to the surface of parietal cells in the stomach. This action helps reduce the production of stomach acid and is commonly used in horses and foals to treat conditions such as gastric ulcers. Therefore, the statement "Omeprazole inhibits the proton pump by binding to the surface of parietal cells of the stomach" is true.

An adsorbent is a substance that has the ability to attract and bind other materials to its surface. This process is known as adsorption. The adsorbent material has a high surface area and can effectively trap and hold molecules or particles from a gas or liquid phase. This property makes adsorbents useful in various applications such as purification, filtration, and separation processes. Therefore, the statement "An adsorbent is a substance that binds other materials to its surface" is true.

Psyllium seed extract is the correct answer because it is a type of bulk forming laxative. Bulk forming laxatives work by absorbing water in the intestine, which increases the bulk of the stool and stimulates bowel movements. Psyllium seed extract is derived from the seeds of the Plantago ovata plant and is commonly used to treat constipation. It is a natural source of dietary fiber and is known for its ability to soften the stool and promote regular bowel movements.

Atropine should not be used in ruminants because it can cause paralytic ileus. Paralytic ileus is a condition where there is a loss of muscle movement in the intestines, leading to a blockage or obstruction. Ruminants, such as cows and sheep, have a unique digestive system that relies on the proper movement of the intestines to process their food. Atropine, a medication that can inhibit muscle movement, can disrupt this process and potentially cause severe digestive issues in ruminants. Therefore, it is true that atropine should not be used in ruminants due to the risk of paralytic ileus.

Because bleach is a caustic substance, you should not administer an emetic like apomorphine. Activated charcoal should be given in this circumstance.

Metoclopramide (Reglan) is a medication that has multiple modes of action. It acts as an anti-emetic by decreasing input into the CRTZ (chemoreceptor trigger zone), which helps to prevent nausea and vomiting. Additionally, it increases contractions in the gastrointestinal tract and promotes gastric emptying. Therefore, the statement that Metoclopramide has three modes of action, including decreasing input into the CRTZ, increasing contractions, and increasing gastric emptying, is true.

H2 blockers are a type of medication that work by blocking the action of histamine on the cells in the stomach lining, which reduces the production of stomach acid. However, they do not have any effect on the acid that has already been produced. Therefore, the statement that H2 blockers prevent acid production but do not neutralize any acid already produced is true.

Diphenhydramine is the correct answer because it is a common active ingredient found in the medication Benadryl. Dimenhydrinate and Meclizine are also active ingredients found in other medications, but they are not specifically associated with Benadryl.

Bismuth subsalicylate (Pepto-bismol) is the correct answer because it can blacken the stool and cause opacities on radiographs. Additionally, it should not be used in cats due to its aspirin-like qualities. Kaolin/pectin and activated charcoal are not mentioned as causing these specific effects.

Metoclopramide (Reglan) is the most commonly used procainamide derivative anti-emetic. This means that it is a medication derived from procainamide and is primarily used to prevent or treat nausea and vomiting. Metoclopramide works by blocking dopamine receptors in the brain, which helps to reduce nausea and increase the movement of food through the stomach. Atropine and Propantheline are not procainamide derivatives and are not commonly used as anti-emetics.

Sucralfate (Carafate) must be given on an empty stomach because it works by forming a protective coating over ulcers or irritated areas in the stomach and intestines. Taking it with food can interfere with its ability to adhere to these areas and may reduce its effectiveness. Therefore, it is important to take sucralfate at least one hour before or two hours after meals to ensure optimal absorption and therapeutic benefit.

Oral ulcers can be a sign of various conditions, including a toxic reaction of the mucosa to BUN, kidney disease, additional presence of stomach ulcers, and NSAID toxicity. These conditions can all contribute to the development of oral ulcers.

Parasympathetic systems are stimulated by cholinergic drugs. Cholinergic drugs act by increasing the levels of acetylcholine, a neurotransmitter involved in the parasympathetic nervous system. These drugs mimic the effects of acetylcholine, leading to increased parasympathetic activity. This can result in various physiological responses such as increased digestion, decreased heart rate, and constriction of the pupils. Therefore, cholinergic drugs are used to treat conditions where increased parasympathetic activity is desired, such as in the management of urinary retention, glaucoma, and certain gastrointestinal disorders.

Apomorphine is the correct answer because it is a medication that is used as an emetic, meaning it induces vomiting. It is available in pill form and can be administered either by dissolving it in a red top tube and giving it as an injection or by directly putting it in the conjunctiva and then removing it after vomiting.

Misoprostol is the correct answer because it suppresses gastric secretions and increases mucus production in the GI tract. This helps to counter the ulcer-causing potential of NSAIDs. Sucralfate is not the correct answer as it works by forming a protective barrier over the ulcers, rather than suppressing gastric secretions. Cimetidine is also not the correct answer as it is a histamine H2 receptor antagonist used to reduce stomach acid production, but it does not increase mucus production.

Metoclopramide is a procainamide derivative. This means that it is derived from procainamide, which is a medication used to treat certain types of irregular heartbeats. Metoclopramide is commonly used to treat gastrointestinal conditions such as nausea, vomiting, and acid reflux. It works by increasing the movement of the stomach and intestines, as well as reducing the sensation of nausea. Being a derivative of procainamide, it shares some similarities in its chemical structure and may have similar effects on certain receptors in the body.

Antacids are commonly used to treat symptoms of gastroesophageal reflux disease (GERD) and peptic ulcers. They work by neutralizing stomach acid, reducing its acidity and providing relief from discomfort.

Activated charcoal is the correct answer because it comes in powdered form and is considered the best adsorbent. It is commonly used to treat poisoning and overdose cases as it can bind to toxins and chemicals in the stomach and prevent their absorption into the bloodstream. Activated charcoal has a large surface area and porous structure, allowing it to effectively adsorb a wide range of substances. It is widely recognized for its ability to alleviate symptoms of gastrointestinal distress, such as bloating, gas, and diarrhea.

Decreases NH4 by absorbing ammonia.

Because of phosphate toxicity.

The answer provided consists of three antihistamines: Dimenhydrinate, Diphenhydramine, and Meclizine. Antihistamines are commonly used to treat allergies and relieve symptoms such as itching, sneezing, and runny nose. Dimenhydrinate is primarily used to prevent and treat motion sickness, while Diphenhydramine is used for allergies, insomnia, and motion sickness. Meclizine is also used to prevent and treat motion sickness, as well as vertigo and dizziness. These medications work by blocking the effects of histamine, a substance in the body that causes allergic symptoms.

H2 receptors are indeed found only in the stomach and are responsible for stimulating the production of stomach acid. These receptors are specifically located on the parietal cells of the stomach lining, which secrete hydrochloric acid. When these receptors are activated, they trigger a cascade of events that result in the release of acid into the stomach, aiding in the digestion of food. Therefore, the statement "H2 receptors are found only in the stomach and cause acid production" is true.

Apomorphine is the correct answer because it stimulates dopamine receptors in the CRTZ (chemoreceptor trigger zone), which is a part of the brain that controls vomiting. By stimulating these receptors, apomorphine induces vomiting. The other options (Acepromazine, Chlorpromazine, and Ipecac syrup) do not have the same mechanism of action and do not specifically target dopamine receptors in the CRTZ.

Antacids do nothing to prevent acid production, rather they act to neutralize the HCl in the stomach.

Anti-constipation

False - because sucralfate only binds mucosa where there is an ulcer.

Ranitidine is the correct answer because it is the only H2 receptor antagonist that also stimulates gastric emptying. Cimetidine and famotidine are H2 receptor antagonists, but they do not have the additional effect of stimulating gastric emptying.

These three drugs, dimenhydrinate, diphenhydramine, and meclizine, are all antihistamines that work by decreasing input to the CRTZ (Chemoreceptor Trigger Zone) from the vestibular apparatus. The CRTZ is a region in the brain that is responsible for triggering nausea and vomiting. By reducing the input from the vestibular apparatus, these drugs help to alleviate symptoms of motion sickness and vertigo.

False - This is a lifelong condition - will need replacement enzymes in order to digest proteins and fats for the rest of its life.

Dimenhydrinate is the correct answer because it is the generic name for the medication Dramamine. Dimenhydrinate is an antihistamine that is commonly used to prevent and treat motion sickness. It works by blocking the effects of histamine in the body, which helps to reduce symptoms such as nausea, dizziness, and vomiting. Diphenhydramine and meclizine are also antihistamines, but they are not the generic name for Dramamine. Therefore, they are not the correct answer.

The drugs Dimenhydrinate, Diphenhydramine, and Meclizine are all used to decrease input to the CRTZ (Chemoreceptor Trigger Zone) from the vestibular apparatus. The CRTZ is an area in the brain that is responsible for triggering the vomiting reflex. By reducing the input from the vestibular apparatus, which is involved in balance and spatial orientation, these drugs can help alleviate symptoms of motion sickness and vertigo.

The correct answer is "All of the above." This means that all three options mentioned - bismuth subsalicylate (Pepto-bismol), kaolin/pectin, and activated charcoal - are considered antidiarrheal drugs. These drugs are commonly used to treat diarrhea by either reducing inflammation in the digestive system (bismuth subsalicylate), absorbing excess fluid in the intestines (kaolin/pectin), or binding to toxins and chemicals in the gut (activated charcoal). Therefore, all three options are correct as they are all used to alleviate symptoms of diarrhea.

Loperamide is a medication used to treat diarrhea by slowing down the movement of the intestines. It is classified as an opioid anti-diarrheal, as it acts on the opioid receptors in the gut to reduce the frequency of bowel movements. Diphenoxylate and paregoric are also opioid anti-diarrheal medications, but loperamide is the most commonly used and widely available option. Therefore, the correct answer is loperamide.

Emollient laxatives contain surfactants that aid in reducing the surface tension of water, allowing it to penetrate and soften the fecal material. This helps to lubricate the stool and promote easier bowel movements.

All of the given options, diphenoxylate, loperamide, and paregoric, are narcotic anti-diarrheal drugs. These drugs are not recommended for use in horses or cattle. The reason behind this is that these drugs can have adverse effects on the gastrointestinal system of these animals and may cause further complications. Therefore, it is important to avoid using these drugs in horses or cattle.

Systemic antacids refer to those that are absorbed into the bloodstream and act throughout the body. These antacids are known for their quick onset and short duration of action, meaning they start working soon after ingestion but their effects do not last for a long time. This is in contrast to non-systemic antacids, which primarily work in the stomach and do not get absorbed into the bloodstream.

Metoclopramide has three modes of action to reduce vomiting. Firstly, it decreases input to the CRTZ (chemoreceptor trigger zone), which is responsible for initiating the vomiting reflex. By reducing the input to the CRTZ, metoclopramide helps to prevent the sensation of nausea and vomiting. Secondly, it increases GI contractions, which promotes the movement of food through the gastrointestinal tract and prevents the buildup of gastric contents that can trigger vomiting. Lastly, metoclopramide increases gastric emptying, meaning that it helps to empty the stomach contents into the intestines more quickly, reducing the likelihood of vomiting.

Cimetidine is the least potent H2 receptor antagonist, followed by ranitidine, and then famotidine, which is the most potent.

MgOH and AlOH are nonsystemic antacids because they work locally in the stomach to neutralize excess acid. They are not absorbed into the bloodstream and do not have systemic effects on the body. CaCO3, on the other hand, is a systemic antacid as it can be absorbed into the bloodstream and can affect the acid-base balance in the body. Therefore, MgOH and AlOH are the correct answers as they are nonsystemic antacids.

Diphenoxylate is a C-V controlled antidiarrheal substance with added atropine. This means that it is a medication used to treat diarrhea and is classified as a controlled substance with a low potential for abuse. Atropine is added to the medication to discourage misuse. Therefore, diphenoxylate is the correct answer as it fits the given description.

These three medications, Acepromazine, Chlorpromazine, and Prochlorpromazine, inhibit dopamine in the CRTZ (chemoreceptor trigger zone) which decreases the stimulation to vomit. Meclizine, on the other hand, is an antihistamine that is commonly used to treat motion sickness and vertigo, but it does not directly inhibit dopamine in the CRTZ.

Paregoric is the correct answer because it is a C-III controlled anti-diarrheal medication that is commonly combined with kaolin/pectin. Diphenoxylate and loperamide are also anti-diarrheal medications, but they are not specifically mentioned in the question as being combined with kaolin/pectin. Therefore, they are not the correct answer.

Ducosate derivatives (DSS) and mineral oil are both examples of emollients. Emollients are substances that help to moisturize and soften the skin. Ducosate derivatives (DSS) are commonly used as stool softeners to relieve constipation. Mineral oil is a type of lubricant that can be applied topically to the skin to prevent dryness and provide a protective barrier. Both of these substances work by trapping moisture in the skin and preventing water loss, making them effective emollients.

An animal with megacolon will likely have a history of constipation, loss of appetite, and vomiting. Megacolon is a condition characterized by the abnormal enlargement of the colon, which can lead to difficulty in passing stool. This often results in constipation, as the stool becomes impacted and cannot be eliminated easily. The loss of appetite can occur due to the discomfort and pain associated with the condition. Vomiting may also be present as a result of the gastrointestinal distress caused by the megacolon.

Opiate/narcotic analgesics are used for diarrheal control because they decrease intestinal secretions and increase segmental contractions. Decreasing intestinal secretions helps to reduce the amount of fluid in the intestines, which can help to alleviate diarrhea. Increasing segmental contractions promotes the movement of stool through the intestines, helping to relieve diarrhea by speeding up the passage of waste material. These mechanisms work together to help control diarrhea and restore normal bowel function.

Kaolin/pectin is both an adsorbent and a protectant. Kaolin is a type of clay that can bind to toxins and irritants in the digestive system, preventing them from being absorbed into the body. Pectin, on the other hand, forms a protective coating on the lining of the stomach and intestines, reducing inflammation and irritation. Therefore, the combination of kaolin and pectin in a medication provides both adsorbent and protective properties, making it an effective treatment for digestive issues.

Atropine is classified as an anticholinergic drug, meaning it blocks the action of acetylcholine, a neurotransmitter that stimulates various processes in the body. By blocking acetylcholine, atropine reduces salivary secretions, which can be beneficial in certain medical procedures or conditions where excessive salivation is a problem. Additionally, atropine decreases peristalsis, the movement of the gastrointestinal tract, and segmentation, the mixing and propulsion of food in the intestines. This can help in conditions where reducing gastrointestinal activity is necessary, such as in the treatment of diarrhea or certain types of abdominal pain.

Aminopentamide and Atropine are both anticholinergic drugs that block the action of acetylcholine in the peripheral nervous system. This decreases the input to the chemoreceptor trigger zone (CRTZ), which is responsible for inducing vomiting. By blocking acetylcholine, these drugs can help prevent vomiting in animals. However, they are contraindicated in animals with glaucoma or pyloric obstruction, as they can worsen these conditions. Therefore, aminopentamide and atropine are the correct answers as they fit the description given in the question.

The treatment of a dog with parvovirus would likely include a combination of anti-emetic, anti-diarrheal, antibiotics, and antacids. Parvovirus in dogs often causes severe vomiting and diarrhea, so anti-emetic drugs can help control the vomiting, while anti-diarrheal drugs can help manage the diarrhea. Antibiotics are necessary to treat any secondary bacterial infections that may occur. Additionally, antacids can be given to help reduce stomach acid and alleviate gastrointestinal discomfort.