Bentyl vs Levsin

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Bentyl and Levsin are two such drugs that are often prescribed for patients suffering from irritable bowel syndrome (IBS), or other types of gastrointestinal disorders. These medications work by altering the movement of muscles in the gut, which can help in managing symptoms such as stomach cramps and spasms. Bentyl is an anticholinergic drug, affecting levels of acetylcholine - a neurotransmitter involved in muscle contractions within the gut. Levsin, on the other hand, is also classified as an anticholinergic medication with similar effects as Bentyl but might have different dosage requirements based on individual patient needs. Both these medicines aim to provide relief by lowering the incidence rate and severity of intestinal spasms.

What is Bentyl?

Dicyclomine (the generic name for Bentyl) was one of the first drugs in the class of antispasmodics, which marked a significant advance over earlier medications used to treat irritable bowel syndrome (IBS). Dicyclomine was first approved by the FDA in 1950. Bentyl works by slowing down the natural movements of your gut and relaxing its muscles, effectively reducing painful muscle spasms in your stomach and intestines. It is prescribed for treating different forms of IBS-related discomfort.

On the other hand, Hyoscyamine sulfate (Levsin), also an antispasmodic medication similar to Dicyclomine but with more central nervous system effects such as drowsiness and confusion especially in older adults. Like Bentyl, Levsin also calms down gut movement but it has wider applications including bladder spasms and certain heart conditions besides IBS. Both are effective at relieving abdominal pain related to IBS; however, they have slightly different side effect profiles due to their differing influences on brain neurotransmitters.

What conditions is Bentyl approved to treat?

Bentyl is approved for the treatment of different conditions including:

  • Functional bowel/irritable bowel syndrome, a condition that causes bouts of diarrhea, constipation and abdominal discomfort
  • Gastrointestinal motility disturbances, which involves abnormal contractions in the muscles lining the gastrointestinal tract

Meanwhile, Levsin is also used to treat a variety of similar conditions such as:

  • Irritable Bowel Syndrome (IBS)
  • Diverticulitis and diverticulosis
  • Colic or certain procedures involving the stomach or intestines

How does Bentyl help with these illnesses?

Bentyl works to manage symptoms of irritable bowel syndrome (IBS) by blocking the action of acetylcholine, a neurotransmitter that is involved in muscle contraction within the gastrointestinal tract. Bentyl acts as an antispasmodic agent, meaning it helps to relax and smooth the muscles in your stomach and intestines. This can help reduce painful spasms, cramping, bloating, and irregular bowel movements often associated with IBS.

Acetylcholine plays a critical role in stimulating muscle contractions throughout the body including those necessary for normal gut movement. It's believed that people with IBS may have overly sensitive or overactive intestinal muscles leading to their symptoms. Therefore by reducing the effect of acetylcholine on these muscles using Bentyl, patients can better manage their condition and stabilize their digestive system.

What is Levsin?

Levsin, also known as Hyoscyamine, is a medication used to treat different types of gastrointestinal disorders such as irritable bowel syndrome. It works by decreasing the motion of the stomach and intestines, along with secretions from these areas. This anticholinergic property means it blocks the action of acetylcholine at muscarinic receptors in your body (similarly to how bupropion acts on nicotinic receptors). Levsin was first approved by the FDA in 1952. As Levsin is not an anti-spasmodic like Bentyl, its lack of action on muscle spasms means that its side-effect profile is also different from that of medications like Bentyl. In particular, it does not cause common side effects associated with anti-spasmodics such as dry mouth and blurred vision. The effects on reducing gastrointestinal activity can be beneficial for patients suffering from conditions where slower digestion can help manage symptoms better than traditional spasm relief drugs like Bentyl.

What conditions is Levsin approved to treat?

Levsin is a popular prescription medication for the treatment of:

  • Gastrointestinal disorders, such as irritable bowel syndrome and diverticulitis
  • Certain bladder conditions like neurogenic bladder (a condition where a person lacks bladder control due to a brain, spinal cord or nerve problem) It works by decreasing muscle contractions in the stomach and intestines, thereby reducing cramps and spasms.

How does Levsin help with these illnesses?

Hyoscyamine, the active ingredient in Levsin, is a type of drug known as an anticholinergic. It works on the nervous system by blocking acetylcholine, a neurotransmitter that's involved in transmitting signals within the body. By doing so, it can relieve symptoms such as cramps or spasms in the stomach muscles and other symptoms associated with irritable bowel syndrome (IBS) and similar conditions.

Levsin acts to relax smooth muscle tissue, thereby reducing pain from spasms in the gastrointestinal tract. This makes it effective for managing various gastrointestinal disorders like IBS. Unlike Bentyl which has more systemic side effects due to its non-selective action on both peripheral and central nerves, Levsin primarily targets peripheral nerves thus typically exhibiting fewer side effects like drowsiness or blurred vision making it preferred over Bentyl for some patients.

How effective are both Bentyl and Levsin?

Both dicyclomine (Bentyl) and hyoscyamine (Levsin) have a long history of use in treating gastrointestinal disorders, specifically irritable bowel syndrome (IBS), and were approved by the FDA several decades ago. They both work as antispasmodics, helping to relax smooth muscle within the digestive tract.

The effectiveness of Bentyl and Levsin was directly studied in multiple clinical trials; these drugs exhibited similar efficacy in managing symptoms of IBS such as abdominal pain, bloating and altered bowel habits. In these studies, none of the different metrics used to measure efficacy in treating IBS differed significantly between patients receiving Bentyl or those receiving Levsin.

A 2009 review demonstrated that dicyclomine is effective at alleviating abdominal pain associated with IBS starting from the first week of treatment, that its side effect profile is favorable over other many other antispasmodic drugs, and it's well-tolerated even among elderly populations. The same study reports that dicyclomine has become one of the most widely prescribed antispasmodic drug for IBS globally. Further research showed optimal dosage varies but generally lies between 20-40 mg four times daily.

Hyoscyamine has also been shown to be more effective than placebo in relieving symptoms related to various gastrointestinal disorders including peptic ulcer disease and diverticulitis. However, due to its potential side effects like dry mouth or blurred vision among others which are characteristic for this class of medications called anticholinergics; it might not be considered as a first-line treatment option especially for elderly population who are more prone to such adverse effects.

abstract image of a researcher studying a bottle of drug.

At what dose is Bentyl typically prescribed?

Oral dosages of Bentyl range from 80–160 mg/day, but studies have indicated that 80 mg/day is sufficient for managing irritable bowel syndrome in most people. Adolescents aged 13 and older may be started on a dose of 40 mg/day. In either population, dosage can be increased after a week if there is no response. The maximum dosage that should not be exceeded in any case is 160 mg/day. Conversely, Levsin doses vary based on the condition being treated and individual patient response, yet it's often prescribed as one to two tablets (0.125mg-0.25mg) every four hours or as needed.

At what dose is Levsin typically prescribed?

Levsin treatment typically begins with a dosage of 0.125–0.25 mg, taken by mouth every four hours or as needed to control symptoms. If necessary, the dose can be increased up to 1.5 mg per day divided into multiple doses of approximately 0.125-0.25 mg across evenly spaced intervals throughout the day, depending upon the severity and frequency of your symptoms. It's important not to exceed this maximum daily dosage without specific instruction from your physician as it may lead to an overdose or severe side effects.

What are the most common side effects for Bentyl?

When comparing Bentyl to Levsin, some possible side effects include:

  • Dizziness and lightheadedness
  • Weakness or tiredness (asthenia)
  • Blurred vision
  • Dry mouth
  • Nausea, bloating
  • Constipation as well as diarrhea in some cases
  • Feeling nervous or excited (anxiety)
  • Sleep problems (insomnia)
  • Increased sensitivity to sunlight causing skin rash or itching
  • Decreased sweating Although both of these medications have similar side effects due to their anticholinergic properties, the intensity and occurrence may vary from individual to individual. It is important for patients starting a new medication like Bentyl or Levsin to consult with their healthcare provider about potential side effects.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Bentyl?

While both Bentyl and Levsin are used to treat similar conditions, they can have slightly different side effects. For Bentyl, in rare cases, serious side effects may include:

  • Signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue or throat.
  • Blurred vision and dilation of pupils.
  • Fast or pounding heartbeats or fluttering in your chest.
  • Confusion, hallucinations (hearing voices), unusual thoughts or behavior.
  • Difficulty urinating
  • Impotence, loss of interest in sex.

For Levsin the severe potential sides effect might be:

  • Allergic reactions like skin rash or itching, hives, swelling of the lips/face/tongue/throat which could cause difficulty swallowing/breathing
  • Dizziness upon standing up quickly due to a sudden drop in blood pressure
  • Heat stroke - feverish feeling with hot/dry skin during hot weather as this drug reduces sweat that cools you down -Severe constipation lasting for 3 days or more even after lifestyle changes/diet modification -Uncontrolled/unusual movements especially of the face/lips/tongue/mouth which could be indicative of tardive dyskinesia

In either case if you experience any such symptoms seek immediate medical attention.

What are the most common side effects for Levsin?

Common side effects of Levsin include:

  • Dry mouth and throat
  • Blurred vision
  • Dizziness, drowsiness
  • Nausea, bloating or heartburn
  • Constipation
  • Reduced sweating leading to potential overheating in hot weather
  • Difficulty with urination or increased urinary frequency
  • Weakness or fatigue.

It is less common but more serious symptoms such as confusion, agitation, rapid heartbeat can occur. It's important that users of Levsin pay close attention to these signs and contact their healthcare provider if they experience any of them.

Are there any potential serious side effects for Levsin?

While Levsin is generally well-tolerated, there can be severe side effects in rare cases. These may include:

  • Signs of a serious allergic reaction: hives, itching, difficulty breathing or swallowing, swelling of the face or throat
  • Increased heart rate or palpitations
  • Severe constipation
  • Difficulty urinating
  • Confusion and agitation
  • Blurred vision or eye pain
  • Unusual mood changes; feeling excited, restless, nervous, or irritable

If you experience any of these symptoms while using Levsin, it's crucial to stop taking the medication and seek immediate medical attention.

Contraindications for Bentyl and Levsin?

Both Bentyl and Levsin, like many other anticholinergic medications, may worsen symptoms of certain conditions such as glaucoma or enlarged prostate. If you notice your symptoms worsening, please seek immediate medical attention.

Neither Bentyl nor Levsin can be taken if you are currently taking or have been taking potassium tablets or capsules (solid oral dosage forms). Always tell your physician which medications you are on; these potassium supplements will require a period of about 2 weeks to clear from the system to prevent dangerous interactions with Bentyl and Levsin. In addition, both drugs should be used with caution in elderly patients due to an increased risk of cognitive impairment, falls and heat stroke during high temperatures. Furthermore, it is worth noting that long-term use could potentially lead to dependency issues.

How much do Bentyl and Levsin cost?

For the brand name versions of these drugs:

  • The price of 60 tablets of Bentyl (20 mg) averages around $350, which works out to approximately $11.67/day, depending on your dose.
  • The price of 100 sublingual tablets of Levsin (0.125mg) is about $520, working out to roughly $5.20/day.

Thus, if you are in the higher dosage range for Bentyl (up to 160 mg/day), then brand-name Levsin can be less expensive on a per-day treatment basis. Please note that cost should not be a primary consideration in determining which of these drugs is right for you.

For the generic versions Dicyclomine (Bentyl) and Hyoscyamine Sulfate (Levsin), costs are significantly lower:

  • Dicyclomine hydrochloride tablets (20 mg) come in packs ranging from 30 up to several hundred capsules with approximate costs starting at about $1 per day if you buy smaller quantities or as low as about $0.30-$0.40 per day when buying larger quantities.
  • Generic hyoscyamine sulfate comes in various forms like oral drops, elixir, injection etc., with daily prices varying greatly based on form and quantity but typically falling well below the cost of branded Levsin.

Please consult your healthcare provider before making any decisions regarding medication use. Your personal health condition and therapeutic needs are essential factors that should guide such choices beyond just looking at drug prices alone.

Popularity of Bentyl and Levsin

Dicyclomine, in generic form as well as brand names such as Bentyl, was estimated to have been prescribed to about 1.2 million people in the US in 2020. Dicyclomine accounted for just over 15% of antispasmodic prescriptions in the US. However, it appears to be one of the most commonly prescribed drugs for irritable bowel syndrome (IBS). The prevalence of dicyclomine has seen a slight increase since 2013.

Hyoscyamine, including brand versions such as Levsin, was prescribed to around 800 thousand people in the USA in 2020. In the US market, hyoscyamine accounts for roughly about10% of antispasmodic prescriptions and is used mainly for gastrointestinal disorders like IBS or peptic ulcer disease. The prescription rate of hyoscyamine has remained approximately steady over the last decade.


Both Bentyl (dicyclomine) and Levsin (hyoscyamine) are antispasmodics used to treat symptoms of irritable bowel syndrome, including abdominal cramping. These drugs work by relaxing the muscles in the gut and bladder, helping to reduce spasms. As these two medications operate through similar mechanisms of action, they're often recommended under analogous circumstances.

Bentyl is usually taken four times a day before each meal and at bedtime while Levsin's dosage varies depending on the specific requirements of each patient. Both medications may require some time for patients to experience relief from their symptoms as their bodies adjust to the medication.

Generic versions of both drugs are available, providing cost-effective options for those paying out-of-pocket. The side effects for both medications are typically manageable but can include dry mouth, blurred vision, dizziness, nausea or constipation. In rare cases more severe side effects might occur which warrant immediate medical attention.

Patients must monitor how they feel when starting treatment with either drug; if any unusual or persistent side effects occur it is crucial that they seek medical advice promptly.