alli (Orlistat 60 mg)

What Is alli and What Is It Used For?

Quick Answer: alli is an over-the-counter weight loss medicine containing orlistat 60 mg. It works by preventing about one quarter of the fat you eat from being absorbed, and is designed for overweight adults with a BMI of 28 or more, used alongside a low-fat, calorie-reduced diet.

alli capsules contain orlistat, a peripherally acting anti-obesity agent that specifically targets fat in the digestive system. Unlike many weight loss supplements that claim to boost metabolism or suppress appetite, orlistat has a well-documented pharmacological mechanism: it inhibits gastrointestinal lipase enzymes, which are responsible for breaking down dietary triglycerides into absorbable fatty acids and monoglycerides. By inactivating these enzymes, approximately 25% of the fat consumed in a meal passes through the gut undigested and is excreted in the stool.

The medication is indicated for weight loss in adults aged 18 years and older who are overweight, defined as having a body mass index (BMI) of 28 or more. BMI is calculated by dividing your weight in kilograms by your height in metres squared. For example, a person who is 170 cm tall would need to weigh at least 81 kg to meet the BMI threshold for alli use. alli is not intended for people who are already at a healthy weight or who are only slightly above normal BMI.

Clinical trials have demonstrated that orlistat, when combined with a reduced-calorie diet, produces significantly greater weight loss than diet alone. The landmark XENDOS (XENical in the prevention of Diabetes in Obese Subjects) trial, a four-year randomised controlled study published in Diabetes Care, showed that orlistat combined with lifestyle modification reduced the incidence of type 2 diabetes by 37% in obese participants. For every 2 kg lost through dietary changes alone, alli can help users lose approximately 1 additional kilogram.

The Health Risks of Being Overweight

Carrying excess weight significantly increases the risk of developing serious health conditions, many of which may not produce noticeable symptoms until they are advanced. These conditions include type 2 diabetes, cardiovascular disease (including coronary artery disease and stroke), hypertension, certain types of cancer (particularly colorectal, breast, and endometrial cancers), osteoarthritis, obstructive sleep apnoea, and non-alcoholic fatty liver disease. Even a modest weight loss of 5-10% of initial body weight has been shown to meaningfully reduce these risks, improve blood lipid profiles, and lower blood pressure according to guidelines from the National Institute for Health and Care Excellence (NICE) and the World Health Organization (WHO).

How alli Works in Your Body

When you eat a meal containing fat, your body releases lipase enzymes from the stomach and pancreas to break down triglycerides into smaller components that can be absorbed through the intestinal wall. Orlistat forms a covalent bond with the active serine residue on these lipase enzymes, permanently inactivating them. The inactivated enzymes can no longer hydrolyse dietary fat, so the intact triglycerides cannot be absorbed and are passed through the digestive tract.

This mechanism is entirely local to the gastrointestinal tract — orlistat has minimal systemic absorption, meaning it does not enter the bloodstream in significant quantities and does not affect the brain, heart, or other organs. This localized action is a key safety advantage compared to centrally acting weight loss agents. However, because undigested fat passes through the intestine, eating high-fat meals while taking alli can lead to gastrointestinal side effects such as oily stools and flatulence, which is why a low-fat diet is essential.

What Should You Know Before Taking alli?

Quick Answer: Do not take alli if you are pregnant or breastfeeding, taking ciclosporin or warfarin, have cholestasis, or have chronic malabsorption syndrome. Consult your doctor if you have diabetes, kidney disease, or take thyroid medications, epilepsy drugs, or HIV medications.

Contraindications

Certain conditions and circumstances make alli unsuitable. You must not take alli in any of the following situations:

• Allergy to orlistat or any other ingredient in the capsules (see What Does alli Contain for a full list of excipients).
• Pregnancy or breastfeeding — weight loss during pregnancy can harm the developing foetus, and it is unknown whether orlistat passes into breast milk.
• Ciclosporin use — orlistat can reduce ciclosporin blood levels, potentially leading to transplant rejection or treatment failure in severe autoimmune conditions.
• Warfarin or other anticoagulants — orlistat may affect vitamin K absorption, altering the effectiveness of blood-thinning medications and increasing bleeding risk.
• Cholestasis — a condition where bile flow from the liver is blocked, which would impair the drug's mechanism of action.
• Chronic malabsorption syndrome — if your body already has difficulty absorbing nutrients, taking a fat-blocking agent could worsen nutritional deficiencies.

Warnings and Precautions

Even if none of the absolute contraindications apply, you should speak with a healthcare provider before starting alli in the following circumstances:

• Diabetes: Weight loss can affect blood sugar levels. Your doctor may need to adjust your diabetes medication (insulin or oral hypoglycaemics) as you lose weight.
• Kidney disease: Orlistat use has been associated with the formation of calcium oxalate kidney stones, particularly in patients with pre-existing chronic kidney disease. Maintaining adequate fluid intake is important.
• Thyroid conditions: If you take levothyroxine, orlistat may reduce its absorption. You may need to take levothyroxine and alli at different times of day, and thyroid function monitoring may be required.
• Epilepsy: There have been reports of changes in seizure frequency in patients taking anti-epileptic medications alongside orlistat. Discuss any changes with your doctor.
• HIV treatment: Orlistat may reduce the absorption of antiretroviral medications. If you are being treated for HIV, consult your healthcare team before starting alli.

Pregnancy and Breastfeeding

Do not take alli if you are pregnant or breastfeeding. Weight loss during pregnancy is generally contraindicated because adequate nutrition is essential for foetal development. If you discover you are pregnant while taking alli, stop taking the capsules immediately and contact your doctor. Women of childbearing potential should note that severe diarrhoea associated with orlistat use may reduce the effectiveness of oral contraceptives; an additional barrier method of contraception is recommended if significant gastrointestinal symptoms occur.

How Does alli Interact with Other Drugs?

Quick Answer: alli has clinically significant interactions with ciclosporin, warfarin, levothyroxine, and oral contraceptives. It can reduce absorption of fat-soluble vitamins. Always tell your doctor about all medications you take before starting alli.

Because orlistat reduces fat absorption, it can also affect the absorption of fat-soluble medications and nutrients. Additionally, some drugs have specific pharmacokinetic interactions with orlistat that require dose adjustments or timing changes. The table below summarises the most important drug interactions.

Major Interactions (Do Not Combine)

Moderate Interactions (Use with Caution)

What Is the Correct Dosage of alli?

Quick Answer: Take one 60 mg capsule three times a day, just before, during, or up to one hour after each main meal. Do not exceed 3 capsules daily. Skip the dose if a meal is missed or contains no fat.

Adults (18 years and older)

The capsules should be taken with meals that contain some fat. If you skip a meal, or if a meal does not contain any fat, you should not take a capsule — alli will have no effect without dietary fat to block. Conversely, eating a meal with too much fat while taking alli significantly increases the likelihood and severity of gastrointestinal side effects. This is why following a low-fat diet is critical to the success of the treatment.

Setting Calorie and Fat Goals

To maximise the effectiveness of alli, you should set daily calorie and per-meal fat targets. Your calorie goal should be approximately 500 calories below what your body needs to maintain your current weight. The following table provides general guidance:

Distribute your fat intake evenly across meals rather than saving your allowance for a single high-fat meal. This approach minimises gastrointestinal side effects and provides better weight loss results. Do not eat less than 1,200 calories per day, as this can lead to nutritional deficiencies.

Children and Adolescents

Elderly

There are no specific dose adjustments for elderly patients. However, older adults should consult their doctor before starting alli, as they may be taking multiple medications and may have reduced kidney or liver function that affects drug safety. Adequate hydration and vitamin supplementation are particularly important in this group.

Missed Dose

If you forget to take a capsule:

• If less than 1 hour has passed since your last main meal, take the missed capsule.
• If more than 1 hour has passed, skip the missed dose and take your next capsule with your next main meal as usual.
• Do not take a double dose to make up for a missed one.

Overdose

Do not take more than 3 capsules per day. Single doses of 800 mg orlistat and multiple doses of up to 400 mg three times daily for 15 days have been studied in normal-weight and obese subjects without significant adverse findings. However, if you believe you have taken too many capsules, contact a healthcare professional or your local poison control centre immediately. Supportive care and monitoring for gastrointestinal symptoms are recommended.

Treatment Duration

alli should not be taken for longer than 6 months. If you have not achieved meaningful weight loss after 12 weeks of consistent use with diet and exercise, you should stop taking alli and consult your doctor or pharmacist. They can help you evaluate whether an alternative approach to weight management may be more appropriate. Successful long-term weight management requires sustained lifestyle changes — including permanent dietary improvements and regular physical activity — not just medication.

What Are the Side Effects of alli?

Quick Answer: The most common side effects are gastrointestinal, including oily or fatty stools, flatulence with oily discharge, urgent bowel movements, and soft stools. These are caused by the drug's fat-blocking mechanism and can be managed by following a low-fat diet.

Like all medicines, alli can cause side effects, although not everyone experiences them. The majority of side effects are related to the drug's mechanism of blocking fat absorption — when undigested fat passes through the intestine, it produces characteristic gastrointestinal symptoms. These effects are generally most pronounced during the first few weeks of treatment, before you have fully adjusted your dietary fat intake.

Effects Seen in Blood Tests

In some patients, blood tests may show elevated liver enzymes. If you are taking warfarin or other anticoagulants, orlistat may affect blood clotting parameters (INR). Always inform your doctor or laboratory that you are taking alli when having blood tests.

How Should You Store alli?

Quick Answer: Store alli below 25°C in the original container, tightly closed. Keep the silica gel desiccants inside the container. Do not use after the expiry date.

Proper storage of alli ensures the capsules remain effective throughout their shelf life. Follow these guidelines:

• Keep out of sight and reach of children.
• Do not use after the expiry date printed on the container and carton (after "EXP"). The expiry date refers to the last day of that month.
• Store at or below 25°C (77°F).
• Keep the container tightly closed, as the capsules are moisture-sensitive.
• The container includes two sealed desiccant canisters containing silica gel to keep the capsules dry. Leave these canisters inside the container. Do not swallow them.
• You can use the blue shuttle case (included in the pack) to carry your daily dose. Discard any capsules stored in the shuttle case for more than 1 month.
• Do not dispose of medicines via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer needed. These measures help protect the environment.

What Does alli Contain?

Quick Answer: Each capsule contains 60 mg of the active ingredient orlistat. The capsules are turquoise with a dark blue band, marked "alli".

Active Ingredient

Each hard capsule contains 60 mg orlistat.

Other Ingredients (Excipients)

The inactive ingredients ensure stability, capsule formation, and identification:

• Capsule contents: Microcrystalline cellulose (E460), sodium starch glycolate, povidone (E1201), sodium lauryl sulfate, talc.
• Capsule shell: Gelatin, indigo carmine (E132), titanium dioxide (E171), sodium lauryl sulfate, sorbitan monolaurate, black ink (shellac, black iron oxide (E172), propylene glycol).
• Capsule band: Gelatin, polysorbate 80, indigo carmine (E132).

Appearance and Pack Sizes

alli capsules have a turquoise shell with a dark blue band around the middle, printed with "alli". Available pack sizes include 42, 60, 84, 90, and 120 capsules. Not all pack sizes may be marketed in every country. A blue shuttle case is included for carrying your daily dose.

BMI Eligibility Guide for alli

Quick Answer: alli is for adults with a BMI of 28 or higher. The table below shows the minimum weight required for each height to meet the BMI 28 threshold.

If your weight is below the minimum listed for your height, you do not meet the BMI threshold for alli use. Consult a healthcare provider for personalised weight management advice.

Frequently Asked Questions About alli