OTC products—especially stimulant laxatives—are meant for very short-term use only, and over-using them could make your constipation worse and lead to very serious medical problems. They can even be addictive.
Also, constipation that won’t clear up may be a symptom of a serious illness, so you have plenty of reason to see your healthcare provider.
Using prescription laxatives under a healthcare provider’s supervision is much safer for long-term use, so if you have regular constipation, this may be a better option for you. Several types are on the market that work differently, so if one type doesn’t work for you, another might.
Uses
Prescription laxatives are most often prescribed for treating:
A change in bowel movement frequency that continues for two weeksNausea, vomiting, or stomach pain with constipationNeed for laxatives for longer than one weekNo bowel movement after taking a laxativeRectal bleeding
Chronic constipation that’s idiopathic (not due to any known cause) Constipation related to a condition, including that from constipation-predominant irritable bowel syndrome (IBS-C) Opioid-induced constipation
Unlike OTC laxatives, prescription drugs aren’t meant for rapid relief of occasional constipation, but rather to keep you regular when constipation is an ongoing problem.
Medications Available
Four classes of prescription laxatives are on the market. Each one works differently and may be prescribed in different situations, depending on what’s believed to be causing your constipation. They are:
Osmotic agentsProkinetic agentsSecretagoguesOpioid antagonists
Osmotic Agents
Available in both OTC and prescription products, osmotic laxatives draw water into the bowel to help soften your stool so it passes more easily.
Osmotics that are available OTC and by prescription include:
Polyethylene glycol (PEG) 3350: Approved for occasional constipation. Brand names include Miralax, GlycoLax, Healthylax, Smooth LAX, Vita Health. Sorbitol: Approved for occasional constipation and irregularity. Brand names include Arlex.
Prescription-only osmotics include:
Cholac/Generlac (lactulose): Approved for constipation, including that related to barium retentionPizensy (lactitol): Approved for chronic idiopathic constipation in adults
Prokinetic Agents
Prokinetic agents cause your gastrointestinal tract to contract and push materials through. The only drug in this class that’s currently available in the United States is:
Motegrity (prucalopride): Approved for chronic idiopathic constipation in adults
This drug is marketed in other countries under the brand name Resolor. It’s also classified as a serotonin receptor agonist.
The similar drug Zelnorm (tegaserod) was withdrawn from the U.S. market in 2007 due to serious cardiovascular side effects; however, Motegrity is not associated with this risk.
Secretagogues
Secretagogues pull more water into the bowel to soften the stool, like osmotics, but through a different mechanism of action. Drugs in this class include:
Amitiza (lubiprostone): Approved for chronic constipation in adults and constipation from IBS-C in adult women Linzess (linaclotide): Approved for chronic constipation, including that from IBS-C, in adults Trulance (plecantide): Approved for chronic constipation in adults
Opioid Antagonists
Opioid painkillers frequently cause constipation. Several medications have been developed to relieve this type of constipation by partially blocking the actions of opioid medications. They include:
Relistor (methylnaltrexone): Approved for opioid-induced constipation (OIC) in adults with non-cancer pain (an injectable form is available for adults in palliative care)Movantik (naloxegol): Approved for opioid-induced constipation in adults with non-cancer painSymproic (naldemedine): Approved for opioid-induced constipation in adults with non-cancer pain
Before Taking
You may want to try lifestyle remedies before turning to laxatives for constipation. These include:
Exercising regularlyDrinking more waterIncreasing dietary fiberNot holding in bowel movements
You shouldn’t use OTC laxatives for more than a week without talking to your healthcare provider. Prescription medications are considered safer for long-term use.
When you go to the healthcare provider for constipation, expect them to ask about your:
Medical history, including medications, medical conditions, previous surgeries, diet, and physical activitySymptoms, including those that may indicate a medical condition such as IBS, pelvic floor dysfunction, or colon cancerStool, including appearance, shape, and consistency
In addition to checking your vital signs and weight, a physical exam for constipation may include:
Pressing on your abdomen to evaluate pain, swelling, and any lumps or massesListening to your intestinal sounds with a stethoscopeExamining your rectum for abnormalitiesChecking anal wink reflexesA digital rectal exam
Your healthcare provider may also order blood tests and imaging studies. A colonoscopy is less common but it may be ordered if certain symptoms are present.
Contraindications
Not all prescription laxatives are safe for everyone. Some medical conditions or other circumstances may make a drug unsuitable for you. These are called contraindications.
GI Problems
If you have a known or suspected intestinal obstruction, your healthcare provider will likely not prescribe any of these drugs for you:
AmitizaLinzessMotegrityMovantikPEGPizensyRelistorSymproicTrulance
GI problems including obstructions, perforations, Crohn’s disease, Hirschsprung’s disease, ulcerative colitis, toxic megacolon/megarectum, irritable bowel syndrome, gut wall disorders, and obstructive ileus are contraindications for:
MotegrityPEG
Kidney Function
Special consideration should be taken for people with impaired kidney function when it comes to:
Movantik (lower dosage required)PEG (used only under a healthcare provider’s supervision)Relistor (lower dosage required)
Dietary Issues
If you have diabetes, caution is urged due to the sugar content of:
Cholac/Generlac
Galactosemia is a condition requiring a special diet that’s low in galactose. These laxatives contain galactose:
Cholac/GenerlacPizensy (lactitol)
If you have fructose intolerance, you should avoid:
Sorbitol
Special Populations
Some prescription laxatives require special monitoring or altered dosages in geriatric (older) people. Your healthcare provider can help guide you to the safest drug for you based on your complete medical history.
Most prescription laxatives are minimally absorbed by the bloodstream, meaning they’re considered safe during pregnancy and breastfeeding. However, for the safety of your child, you should check with your healthcare provider about any drugs you’re considering.
Other
If you’re having surgery, you should avoid Cholac/Generlac beforehand.
If you take a strong CYP3A4 inhibitor drug (such as clarithromycin or ketoconazole), you shouldn’t take Movantik. Symproic may interact negatively with these medications as well.
If you have anuria (failure of kidneys to produce urine), you shouldn’t take sorbitol.
Side Effects and Warnings
Each class of laxatives is associated with certain side effects and warnings. Individual medications may have some or all of those listed here and may also be associated with others; be sure you’re familiar with all the possible risks of any medication you’re taking.
Osmotics
Common side effects of osmotic laxatives include:
NauseaBloatingCrampingFlatulenceDiarrhea
Potentially serious side effects include:
DehydrationElectrolyte imbalance
Prokinetics
Common side effects of Motegrity include:
HeadacheAbdominal painNauseaDiarrheaAbdominal distentionDizzinessVomitingFlatulenceFatigue
Motegrity comes with a warning about worsening depression and the emergence of suicidal thoughts and behaviors. You should stop taking this medication right away and contact your healthcare provider if you experience this.
Secretagogues
Common side effects of secretagogues include:
Diarrhea, which may be severeNauseaHeadacheAbdominal pain and distentionFlatulence
Opioid Antagonists
Common side effects of opioid antagonists include:
Abdominal painDiarrheaNauseaHeadacheFlatulenceVomiting
These drugs also carry warnings about the possibility of gastrointestinal perforation in people with known or suspected lesions in the GI tract.
A Word From Verywell
Because it could be a symptom of a more serious problem, be sure to let your healthcare provider know about your constipation, especially if it lasts more than a few days or returns frequently.
Trouble breathingHivesSwellingTightness in the throatHoarse voiceNausea or vomitingAbdominal painDizziness or faintingRapid heartbeatChest pain
You don’t have to suffer from constipation. If you have regular or long-lasting bouts, prescription laxatives may be a safer and more effective option for you than over-the-counter medications.
