Drugs Affecting Gastrointestinal Motility

Okay, here's a simplified version of the notes on drugs affecting gastrointestinal (GI) motility:

### How Drugs Affect Your Gut's Movement

• Drugs Can:
  • Speed up your bowels if you're constipated.
  • Make your gut work better overall.
  • Slow down your bowels if you have diarrhea, so you absorb more nutrients.

### Where Drugs Work

• Drugs work in different parts of your gut:
  • Some, like bismuth subsalicylate, work right in the gut.
  • Others affect nerves that control your gut.
  • Some, like metoclopramide, get your gut moving.
  • Bulk laxatives add fiber to help you go.
  • Anti-diarrheal medicines slow things down.
  • Lubricants make things slippery.
  • Stimulant laxatives make your gut muscles contract.

### Laxatives and Anti-Diarrheals for Different Ages

Children

• Don't use laxatives all the time.
• Start with good food, water, and regular toilet times.
• Glycerin suppositories are good for little kids.
• Older kids can use lubricants, but avoid strong stimulants.
• For kids who can't control their bowels, senna or mineral oil might help for a bit, but see a doctor.
• Kids over 2 can use loperamide for diarrhea, but watch for dehydration.
• Don't give bismuth subsalicylate to kids with fever because of Reye's syndrome.
• Always give the right dose of medicine.

Adults

• Don't get hooked on laxatives.
• Eat well, exercise, and drink plenty of water.
• Take anti-diarrheals as directed and don't overdo it.
• Be careful when pregnant or breastfeeding; ask a doctor. Stool softeners are often used after giving birth.
• Medicines can get into breast milk and affect the baby's gut, so be cautious.

Older Adults

• Watch out for side effects like feeling sleepy, confused, dizzy, or off-balance.
• These can lead to falls, so be careful.
• Some medicines can cause constipation.
• Kidneys and liver might not work as well, so doses may need to be adjusted.
• Psyllium is good because it can also help with cholesterol.
• Drink lots of water to avoid dehydration.
• Stay active and eat lots of fiber.
• Stick to your routine, even when sick or in the hospital.

### Laxatives

• Use them briefly for constipation, to avoid straining, to clean out your bowels for tests, or to remove poisons.
• Most are over-the-counter.
• You can become dependent on them.

### Types of Laxatives

• Stimulants: Irritate your gut.
• Bulk-forming: Add bulk to your stool.
• Osmotic: Pull water into your gut.
• Lubricants: Make things slippery.
• New laxatives: Change how your body absorbs sodium or affect pain receptors.

### Chemical Stimulants

• Make nerves in your gut move things along.
• Examples: bisacodyl, castor oil, senna

Don't Use If:

• You're allergic.
• You have serious stomach problems.
• Pregnant women shouldn't use castor oil.

Be Careful If:

• You have heart problems.
• You have stomach pain, feel sick, or are throwing up.
• You're pregnant or breastfeeding.

### Senna (a Chemical Stimulant Laxative)

• Why Use It: For short-term constipation or bowel issues.
• How It Works: Makes your gut muscles move.
• What to Watch For: Diarrhea, cramps, irritation.

### Bulk-Forming Laxatives

• Make your stool bigger.
• Examples: methylcellulose, polycarbophil, psyllium

Don't Use If:

• You're allergic.
• You have serious stomach problems.
• You have an infection.
• You have a blockage, tear, or bleeding in your gut.

Side Effects

• Diarrhea, cramps, feeling sick
• Dizziness, headache, feeling weak
• Sweating, heart racing, flushing, fainting
• Drink lots of water with these.

Drug Interactions

• Can interfere with other medications.

### Psyllium (a Bulk-Forming Laxative)

• Why Use It: For occasional constipation; might lower cholesterol.
• How It Works: Adds bulk, pulls in fluid, and gets your gut moving.
• What to Watch For: Diarrhea, cramps, bloating, irritation.

### Osmotic Laxatives

• Pull water into your gut.
• Examples: lactulose, magnesium citrate, magnesium hydroxide, polyethylene glycol

### Magnesium Citrate (an Osmotic Laxative)

• Why Use It: For short-term constipation, to avoid straining, or to clean out your bowels.
• How It Works: Adds fluid to your stool, making it bigger and easier to pass.
• What to Watch For: Diarrhea, cramps, bloating, irritation.

### Lubricants

• Make pooping easier without making your gut move.
• Good for people with hemorrhoids or after surgery.
• Examples: docusate, glycerin, mineral oil

How They Work

• Docusate: Softens stool.
• Glycerin: Gently empties your rectum.
• Mineral oil: Coats your stool.

Why Use Them

• For short-term constipation.

Be Careful If:

• You're allergic.
• You have stomach problems.
• You're pregnant or breastfeeding.

### Docusate (a Lubricant)

• Why Use It: If you shouldn't strain (like after surgery) or for short-term constipation.
• How It Works: Makes stool slippery and keeps it from drying out.
• What to Watch For: Diarrhea, cramps, bloating, irritation, leakage.

### Opioid Antagonists

• Can help with constipation caused by strong pain medicines.

How They Work

• Block the effects of opioids in your gut.

Why Use Them

• To treat constipation from opioids.

Side Effects

• Stomach pain, diarrhea, feeling sick, dizziness, gas, headache.
• Watch for withdrawal symptoms.
• Tell your doctor if you have severe stomach pain.

Drug Interactions

• Other opioid antagonists.

### Methylnaltrexone Bromide (an Opioid Antagonist)

• Why Use It: To treat opioid-induced constipation.
• What to Watch For: Stomach pain, diarrhea, headache, sweating, anxiety.

### Gastrointestinal Stimulants

• Make your whole gut work better.
• Example: metoclopramide

How They Work

• Stimulates gut activity.
• Increases gut juices and movement.
• Makes your gut more sensitive.

Why Use Them

• When you need to move food through your gut quickly.

Don't Use If:

• You're allergic.
• You have a blockage or bleeding in your gut.

Be Careful If:

• You're pregnant or breastfeeding.

Side Effects

• Lower blood pressure and heart rate
• Weakness, tiredness, and sleepiness
• Dry mouth
• Feeling sick
• Movement problems

### Metoclopramide (a Gastrointestinal Stimulant)

• Why Use It: For heartburn, nausea, vomiting, stomach problems from diabetes, or to help move things along during tests.
• How It Works: Gets your gut moving without extra juices; makes your gut more sensitive.
• What to Watch For: Restlessness, sleepiness, tiredness, movement problems, seizures, nausea, and diarrhea.

### Anti-Diarrheals

• Slow down your gut to stop diarrhea.
• Examples: bismuth subsalicylate, loperamide, opium derivatives

How They Work

• Slow down gut movement.
  • Bismuth subsalicylate: Works on the gut lining.
  • Loperamide: Works on gut muscles.
  • Opium derivatives: Work on the brain to slow things down.

Don't Use If:

• You're allergic.

Be Careful If:

• You're pregnant or breastfeeding.
• You have a blockage in your gut.
• You have diarrhea from poison.
• You have liver problems.

Side Effects

• Constipation
• Stomach discomfort
• Feeling sick
• Dry mouth
• Fatigue, Weakness and dizziness

### Loperamide (an Anti-Diarrheal)

• Why Use It: To control diarrhea or reduce output from ileostomies.
• How It Works: Slows down gut movement.
• What to Watch For: Stomach pain, dry mouth, feeling sick, constipation, dizziness, tiredness, drowsiness.

**### Alosetron (