Senna-Lax 8.6mg Tablets
It is used to treat constipation.
Drug Class
Laxative
Pharmacologic Class
Stimulant laxative; Anthraquinone derivative
Pregnancy Category
B
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Senna is a type of laxative that helps stimulate your bowels to move stool. It's used for occasional constipation and usually works within 6 to 12 hours after you take it. It's important to drink plenty of fluids while using this medicine.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely.
When taking this medication, keep the following guidelines in mind:
- Do not take any other medications within 2 hours of taking this drug.
- If you are taking this medication once a day, take it at bedtime.
- Swallow the tablet whole; do not chew, break, or crush it.
- Take the medication with a full glass of water.
Storing and Disposing of Your Medication
To ensure the quality and safety of your medication:
- Store it at room temperature in a dry place, avoiding the bathroom.
- Protect the medication from heat sources.
- Keep all medications in a safe location, out of the reach of children and pets.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely.
When taking this medication, keep the following guidelines in mind:
- Do not take any other medications within 2 hours of taking this drug.
- If you are taking this medication once a day, take it at bedtime.
- Swallow the tablet whole; do not chew, break, or crush it.
- Take the medication with a full glass of water.
Storing and Disposing of Your Medication
To ensure the quality and safety of your medication:
- Store it at room temperature in a dry place, avoiding the bathroom.
- Protect the medication from heat sources.
- Keep all medications in a safe location, out of the reach of children and pets.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Drink plenty of fluids (6-8 glasses of water daily) to help prevent dehydration and aid bowel movements.
- Increase dietary fiber intake (fruits, vegetables, whole grains) to promote regular bowel function.
- Engage in regular physical activity to help stimulate bowel motility.
- Do not use this product for more than 7 days unless directed by a doctor.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
17.2 mg (two 8.6 mg tablets) once daily, preferably at bedtime
Dose Range:
8.6 - 34.4 mg
Condition-Specific Dosing:
occasionalConstipation:
Initial dose 8.6 mg to 17.2 mg once daily; may increase up to 34.4 mg per day in divided doses if needed. Do not exceed 34.4 mg in 24 hours.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Children 2 to under 6 years: 4.3 mg once daily, max 8.6 mg/day. Children 6 to under 12 years: 8.6 mg once daily, max 17.2 mg/day. Not recommended for children under 2 years without medical supervision.
Adolescent:
Children 12 years and older: Same as adult dosing (8.6 mg to 17.2 mg once daily, max 34.4 mg/day).
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed
Moderate:
No specific adjustment needed
Severe:
Use with caution; increased risk of electrolyte imbalance (e.g., hypokalemia) due to potential for fluid loss. Monitor electrolytes.
Dialysis:
Considerations: Use with caution due to potential for fluid and electrolyte disturbances. Consult nephrologist.
Hepatic Impairment:
Mild:
No specific adjustment needed
Moderate:
No specific adjustment needed
Severe:
No specific adjustment needed
Pharmacology
Mechanism of Action
Sennosides are prodrugs that are metabolized by colonic bacteria into active anthrones (e.g., rhein anthrone). These active metabolites stimulate the colon's motility (peristalsis) and increase water and electrolyte secretion into the bowel lumen, leading to a laxative effect.
Pharmacokinetics
Absorption:
Bioavailability:
Poorly absorbed in the upper gastrointestinal tract; active metabolites are formed in the colon.
Tmax:
Active metabolites (rhein) appear in plasma after 6-10 hours.
FoodEffect:
Minimal impact on efficacy; can be taken with food to reduce gastrointestinal upset.
Distribution:
Vd:
Not available
ProteinBinding:
Not available
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 16 hours (for rhein)
Clearance:
Not available
ExcretionRoute:
Primarily fecal (unabsorbed drug and metabolites); small amount of active metabolites excreted renally.
Unchanged:
Minimal systemic absorption of unchanged sennosides.
Pharmacodynamics
OnsetOfAction:
6-12 hours
PeakEffect:
8-12 hours
DurationOfAction:
Effects typically resolve within 24 hours after a single dose.
Confidence:
Medium
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
If you experience any of the following symptoms, call your doctor immediately or seek emergency medical attention, as they may be signs of a severe and potentially life-threatening reaction:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Other Possible Side Effects
Like all medications, this drug can cause side effects, although not everyone will experience them. Many people have either no side effects or only mild ones. If you are bothered by any of the following side effects or if they do not go away, contact your doctor for advice:
- Stomach pain or cramps.
Note: This list does not include all possible side effects. If you have concerns about side effects, consult your doctor. For medical advice regarding side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
If you experience any of the following symptoms, call your doctor immediately or seek emergency medical attention, as they may be signs of a severe and potentially life-threatening reaction:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Other Possible Side Effects
Like all medications, this drug can cause side effects, although not everyone will experience them. Many people have either no side effects or only mild ones. If you are bothered by any of the following side effects or if they do not go away, contact your doctor for advice:
- Stomach pain or cramps.
Note: This list does not include all possible side effects. If you have concerns about side effects, consult your doctor. For medical advice regarding side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe abdominal pain or cramping
- Nausea or vomiting
- Rectal bleeding
- No bowel movement after using the laxative for several days
- Signs of dehydration (e.g., dry mouth, excessive thirst, decreased urination, dizziness, lightheadedness)
- Muscle weakness or cramps
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
If you are experiencing any of the following health issues:
+ Bowel blockage
+ Abdominal pain
+ Upset stomach
+ Rectal bleeding
+ Vomiting
+ Changes in bowel habits that have lasted for more than 2 weeks
Please note that this is not an exhaustive list of all potential interactions with this medication. Therefore, it is crucial to discuss all of your:
Medications (prescription and over-the-counter)
Natural products
Vitamins
Health problems
with your doctor and pharmacist to ensure safe use. Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor to confirm that it is safe to do so in conjunction with this medication.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
If you are experiencing any of the following health issues:
+ Bowel blockage
+ Abdominal pain
+ Upset stomach
+ Rectal bleeding
+ Vomiting
+ Changes in bowel habits that have lasted for more than 2 weeks
Please note that this is not an exhaustive list of all potential interactions with this medication. Therefore, it is crucial to discuss all of your:
Medications (prescription and over-the-counter)
Natural products
Vitamins
Health problems
with your doctor and pharmacist to ensure safe use. Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor to confirm that it is safe to do so in conjunction with this medication.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Do not exceed the recommended duration of use, which is 1 week, unless your doctor specifically instructs you to do so. Additionally, refrain from using other laxatives or stool softeners concurrently with this drug, unless advised by your doctor. If you experience rectal bleeding or fail to have a bowel movement after using this medication, consult your doctor promptly. If you are pregnant, planning to become pregnant, or are breastfeeding, discuss this with your doctor to carefully weigh the benefits and risks of using this medication to you and your baby.
Overdose Information
Overdose Symptoms:
- Severe diarrhea
- Abdominal cramps
- Nausea
- Vomiting
- Significant fluid and electrolyte imbalance (especially hypokalemia)
- Dehydration
What to Do:
Discontinue use immediately. Rehydrate with fluids and electrolytes. Seek immediate medical attention. In case of overdose, call a Poison Control Center at 1-800-222-1222.
Drug Interactions
Contraindicated Interactions
- Intestinal obstruction
- Acute abdominal pain of unknown origin
- Appendicitis
- Undiagnosed rectal bleeding
- Severe dehydration
Major Interactions
- Digoxin (increased risk of digoxin toxicity due to hypokalemia)
- Diuretics (thiazide, loop diuretics - increased risk of hypokalemia)
- Corticosteroids (increased risk of hypokalemia)
Moderate Interactions
- Antiarrhythmics (increased risk of arrhythmias due to hypokalemia)
Monitoring
Routine Monitoring
Bowel movements
Frequency: Daily, during use
Target: Regular, soft stool
Action Threshold: No bowel movement after 2-3 days of use, or persistent diarrhea/cramping.
Electrolytes (Potassium)
Frequency: As clinically indicated, especially with prolonged use or in at-risk patients (e.g., renal impairment, concomitant diuretic use)
Target: 3.5-5.0 mEq/L
Action Threshold: Potassium < 3.5 mEq/L or symptoms of hypokalemia (muscle weakness, cramps, fatigue).
Hydration status
Frequency: Daily, during use
Target: Adequate fluid intake, no signs of dehydration
Action Threshold: Signs of dehydration (dry mouth, decreased urination, dizziness).
Symptom Monitoring
- Severe abdominal pain
- Cramping
- Nausea
- Vomiting
- Rectal bleeding
- No bowel movement after use
- Signs of dehydration (e.g., dry mouth, excessive thirst, decreased urination, dizziness, lightheadedness)
- Muscle weakness or cramps (signs of hypokalemia)
Special Patient Groups
Pregnancy
Generally considered safe for short-term use for occasional constipation during pregnancy. Bulk-forming laxatives are often preferred as first-line therapy. Use with caution and under medical advice.
Trimester-Specific Risks:
First Trimester:
Low risk for short-term use.
Second Trimester:
Low risk for short-term use.
Third Trimester:
Low risk for short-term use.
Lactation
Minimal amounts of active metabolites are excreted into breast milk. Generally considered compatible with breastfeeding for short-term use. Monitor the infant for diarrhea.
Infant Risk:
Low risk of adverse effects; monitor for loose stools or diarrhea in the infant.
Pediatric Use
Use with caution and strictly adhere to age-specific dosing. Not recommended for children under 2 years without medical supervision. Prolonged use can lead to laxative dependence and electrolyte imbalance.
Geriatric Use
Start with the lowest effective dose. Elderly patients may be at increased risk of dehydration and electrolyte imbalance (especially hypokalemia) due to age-related changes in renal function and fluid balance. Monitor closely for adverse effects.
Clinical Information
Clinical Pearls
- Senna is a stimulant laxative best suited for short-term relief of occasional constipation, not for chronic use or weight loss.
- Prolonged or excessive use can lead to laxative dependence, electrolyte disturbances (especially hypokalemia), and melanosis coli (a benign pigmentation of the colon).
- Advise patients to ensure adequate fluid intake to prevent dehydration while using senna.
- Due to its 6-12 hour onset of action, senna is often taken at bedtime for a morning bowel movement.
- Educate patients that abdominal cramping is a common side effect, especially with higher doses.
Alternative Therapies
- Bulk-forming laxatives (e.g., psyllium, methylcellulose)
- Osmotic laxatives (e.g., polyethylene glycol, magnesium hydroxide, lactulose)
- Stool softeners (e.g., docusate sodium)
- Lubricant laxatives (e.g., mineral oil)
- Peripherally acting mu-opioid receptor antagonists (PAMORAs) for opioid-induced constipation (e.g., methylnaltrexone, naloxegol)
Cost & Coverage
Average Cost:
$5 - $15 per 100 tablets (8.6mg)
Generic Available:
Yes
Insurance Coverage:
Over-the-counter (OTC), generally not covered by insurance unless prescribed by a physician.
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.