Contrave (Bupropion + Naltrexone) — Patient Guide (Australia)

Contrave is a combination medicine used to support weight management in adults. It contains two active ingredients:

• Bupropion
• Naltrexone

This page explains how Contrave works, how it’s usually taken, timing and food interactions, safety considerations, and practical tips. It’s designed to be easy to understand, but it does not replace advice from a healthcare professional.

Basic product information

Indications (when Contrave may be used)

In Australia, Contrave is commonly used to support weight management in adults who:

• Have body weight above a clinically significant range (often described using BMI criteria), and/or
• Have weight-related health risks such as type 2 diabetes, dyslipidaemia, or high blood pressure, depending on clinical assessment.

Important: Contrave is not a quick fix. It is intended to be used alongside changes to diet, physical activity, and behaviour strategies. Your doctor will decide whether it’s appropriate based on your medical history and current medicines.

How Contrave works (mechanism of action)

Contrave combines two medicines with complementary actions in the brain:

• Bupropion: increases the activity of certain brain chemicals involved in appetite regulation (commonly described as influencing norepinephrine and dopamine pathways). This can help reduce hunger and cravings and may improve motivation for healthier behaviour.
• Naltrexone: blocks opioid receptors. Opioid signalling is involved in reward and appetite-related pathways. Blocking these receptors may help reduce “food reward” and binge/craving behaviours in some people.

Overall effect: Many people experience improved appetite control and reduced cravings, which supports calorie reduction and gradual weight loss when combined with lifestyle measures.

Pharmacokinetics (how the body handles the medicine)

Pharmacokinetics describes what happens to a medicine after you take it—absorption, metabolism, and elimination. Exact values can vary between individuals.

Absorption

• Bupropion and naltrexone are absorbed after oral dosing.
• Because Contrave uses a titration schedule, blood levels build as the dose is increased.

Metabolism

• Bupropion is metabolised mainly by liver enzymes (including CYP2B6), producing active metabolites such as hydroxybupropion and others.
• Naltrexone is metabolised primarily by the liver to an active metabolite (6β-naltrexol).

Elimination

• Both the parent compounds and metabolites are eliminated mainly through the body’s usual routes (including via urine), with elimination affected by liver and kidney function.

Why this matters: If you have liver impairment, take medicines that affect metabolism, or have significant kidney issues, your healthcare team may adjust monitoring or avoid certain combinations.

Typical use and treatment goals

Contrave is typically used as part of a structured weight management plan, which often includes:

• Calorie-aware eating (e.g., portion control or energy deficit)
• Regular physical activity (aerobic + resistance as appropriate)
• Behaviour strategies (sleep, stress management, craving coping plans)
• Ongoing progress reviews

Your prescriber will typically set practical, measurable goals. Treatment may be reviewed at intervals (for example, assessing progress after an initial period of titration and early maintenance).

How to take Contrave (timing and titration)

Contrave is commonly started with a gradual dose build-up (titration) to reduce side effects such as nausea, headache, or sleep disturbance. The exact schedule can vary depending on the specific product strengths and local guidance, so follow the instructions given to you.

When to take your doses

• Contrave tablets are usually taken once or twice daily depending on the stage of titration.
• To reduce sleep-related side effects, a dose later in the day may need to be avoided—your prescriber may recommend taking it earlier.

Swallowing tips

• Swallow tablets whole with water.
• Do not crush or chew unless specifically instructed.

What to do if you miss a dose

• Take it when you remember if it is close to the next scheduled dose.
• If it’s almost time for the next dose, skip the missed dose and continue your normal schedule.
• Do not double up.

Note: If you repeatedly miss doses or stop for an extended period, you may need a restart plan—seek advice from your healthcare team.

Food interactions

Food can influence comfort and absorption timing for some medicines, and it can affect nausea, which is a common early side effect.

• General advice: If you experience nausea, consider taking Contrave with food or after a meal (unless your clinician advised otherwise).
• Try to maintain a consistent routine (e.g., with the same type of meal each day) to improve tolerability.
• Avoid very heavy or fatty meals if they worsen reflux or nausea for you.

Alcohol and hydration can also affect how you feel—see the sections below.

Alcohol and medicine interactions

Alcohol

Because Contrave includes bupropion, caution is advised with alcohol. Alcohol may increase the risk of seizures and may worsen side effects such as dizziness, drowsiness, or mood changes.

• If you drink alcohol, consider reducing intake and avoid binge drinking.
• Discuss your alcohol use openly with your healthcare professional.
• If you have a history of alcohol dependence or withdrawal, seek medical advice before starting or adjusting Contrave.

Important medicine interactions

Contrave can interact with several medication groups. This is not an exhaustive list—always provide your healthcare professional and pharmacist with a full list of:

• Prescription medicines
• Over-the-counter medicines
• Herbal products (e.g., St John’s wort)
• Supplements

Key interaction areas:

• Other medicines that lower seizure threshold (e.g., some antidepressants or antipsychotics, stimulants, or medicines that cause withdrawal-like effects) may increase seizure risk.
• Monoamine oxidase inhibitors (MAOIs): combining may be unsafe. There are also “washout” periods when switching between MAOIs and other antidepressant-type medicines.
• Naltrexone and opioid medicines: naltrexone can block opioid effects. This may reduce the effectiveness of opioid pain medicines (including some cough suppressants or medicines containing opioids). It can also complicate emergency pain management.
• Medicines affecting liver enzymes (such as CYP2B6 inhibitors/inducers) may alter bupropion exposure and side effects.
• Antidepressants and other mood-altering medicines: combining can increase the risk of certain mental health effects or additive side effects.
• Blood pressure and heart-rate medicines: Contrave may increase blood pressure and heart rate in some people, so your prescriber may monitor closely if you take cardiovascular medicines.

Always seek advice if you use opioid medicines, require surgery, or have been prescribed stronger pain relief. Tell healthcare staff you are taking Contrave.

Dosing (what patients should know)

Dose is individualised and usually increased over time (titration) to improve tolerability. While exact titration schedules can vary, the general concept is:

• Start with a lower dose
• Increase stepwise over several weeks
• Reach a target maintenance dose if tolerated

Do not change your dose or stop/start without advice, because side effects and safety risks can be higher if the schedule isn’t followed.

Missed titration doses: If you have missed several doses or stopped for a prolonged period, your prescriber may recommend restarting at a lower step and building up again.

Safety profile (common side effects and when to seek help)

Like all medicines, Contrave can cause side effects. Many are dose-related and improve as your body adjusts, but some require medical attention.

Common side effects

• Nausea
• Headache
• Dry mouth
• Constipation or other stomach discomfort
• Insomnia or disturbed sleep
• Dizziness
• Increased blood pressure or heart rate in some people

Less common but serious risks

• Seizures (risk increases with factors that lower seizure threshold, excessive alcohol use/withdrawal, or certain drug combinations)
• Mood changes including worsening depression, anxiety, agitation, or suicidal thoughts—seek urgent help if these occur
• Allergic reactions (e.g., rash, swelling, trouble breathing)
• Suicidality warning in relevant populations: if you notice concerning mood or behavioural changes, contact a healthcare professional promptly
• Serious liver-related issues: report symptoms such as yellowing of the skin/eyes, dark urine, severe fatigue
• Opioid interaction challenges: naltrexone blocks opioid effects, which may lead to inadequate pain control if opioids are needed

Urgent guidance: If you experience seizure activity, severe allergic symptoms, chest pain, fainting, or significant mental health changes, seek urgent medical attention immediately.

Practical use tips (to help you get the best results)

• Start low, go slow: follow the titration plan. Most uncomfortable side effects are easier to manage during gradual dose increases.
• Plan around sleep: if you feel wired or have insomnia, take your dose earlier (discuss with your prescriber).
• Manage nausea: take with food if advised/if it suits you; smaller meals and slower eating can help.
• Monitor blood pressure: especially if you have hypertension or take related medicines.
• Keep a symptom diary: note appetite changes, mood, sleep, headaches, and any stomach issues so you can discuss adjustments early.
• Avoid abrupt alcohol changes: consistent, moderate use—or abstinence if recommended—reduces risk.
• Review your medication list: check OTC products and supplements for hidden ingredients (including stimulants or opioid-containing products).
• Combine with lifestyle changes: Contrave works best when paired with a structured plan.

Who should be extra cautious?

You may need extra monitoring or an alternative approach if you have:

• A history of seizures, significant head injury, or conditions that increase seizure risk
• Significant alcohol dependence or frequent heavy alcohol intake
• Significant liver impairment
• A current requirement for opioid medicines for pain or cough
• Uncontrolled high blood pressure or significant cardiovascular disease
• Current or past mood disorders, especially if you’ve had severe depression or bipolar disorder

Always ensure your clinician knows your full medical history.

Alternative options for weight management

Depending on your clinical situation, there are multiple non-medicine and medicine options for weight management. Your healthcare team can help choose the most suitable approach.

Non-medicine alternatives

• Structured diet and activity programs (including referral to a dietitian)
• Behaviour change coaching (goal setting, trigger management, habit building)
• Sleep and stress interventions to support hunger regulation

Medicine alternatives (examples)

• Other anti-obesity medicines available in Australia may be considered based on eligibility and risk profile
• Some people may be advised on medicines primarily for related conditions (e.g., type 2 diabetes medications) that also influence weight—this is individualised

Important: Alternatives depend on availability, medical criteria, and your health history. Discuss options with your healthcare professional.

Market and legal context in Australia

In Australia, medicines are regulated under the Australian Therapeutic Goods framework. Weight management treatments that contain active pharmaceutical ingredients are subject to prescribing and safety requirements. Access may differ depending on whether the product is listed for certain indications and how it is supplied through pharmacy channels.

Healthcare professionals consider factors such as:

• Eligibility criteria for weight management medicines
• Potential medicine interactions
• Monitoring needs (e.g., blood pressure, mood changes)
• Individual risk factors

Pharmacy supply: You can typically obtain medicines through approved pharmacy distribution pathways. Availability can vary by brand, pack size, and supply chain factors.

Recent guidance and monitoring (what to expect)

Across weight management medicines, general best practice includes:

• Baseline assessment (BMI/weight-related health risks, medical history, current medicines)
• Titration and side-effect management during the early weeks
• Regular follow-up to check tolerability and adherence
• Progress evaluation after an initial period to determine whether continued treatment is appropriate
• Ongoing lifestyle support rather than using medication alone

Your prescriber may also recommend monitoring for blood pressure, mental health symptoms, and changes in appetite or cravings.

Delivery and availability (online pharmacy)

Availability and delivery times can vary across Australia depending on local stock, supplier dispatch schedules, and courier services. Many online pharmacies offer:

• Home delivery to many Australian postcodes
• Tracking and estimated delivery windows
• Discreet packaging

Tips for ordering:

• Allow time for dispatch and delivery, especially for ongoing monthly refills.
• Check whether you need to provide documentation or complete any required steps for supply via your chosen pharmacy platform.
• Keep your medication in its original packaging, store at recommended temperatures, and follow any label instructions.

Frequently Asked Questions (FAQ)

1) How long does it take for Contrave to work?

Many people notice appetite and craving changes during titration, but meaningful weight changes typically develop over weeks to months. Your clinician will assess your response after an appropriate trial period and decide whether to continue.

2) What should I do if I feel nauseous?

Nausea is common early on. Taking the dose with food (if suitable for you), eating smaller meals, and following the titration schedule can help. If nausea is severe, persistent, or you can’t keep fluids down, contact your healthcare professional.

3) Can I drink alcohol while taking Contrave?

It’s best to be cautious. Alcohol may increase seizure risk and can worsen side effects. Discuss your alcohol intake with your healthcare professional, especially if you drink heavily or have a history of alcohol dependence.

4) Will Contrave affect opioid pain medicines?

Yes. Naltrexone can block opioid receptors, which may reduce or block the effects of opioid medicines. If you use opioids for pain or cough—or may need them for surgery or emergencies—tell your healthcare team that you are taking Contrave.

5) What if I miss a dose?

Take the missed dose only if it’s close to the next scheduled dose and follow your clinic’s guidance. Otherwise, skip it and continue as prescribed. Do not double up.

6) Can Contrave be taken with other antidepressants?

Some combinations may be unsafe or require careful monitoring due to effects on mood and seizure risk. Always review your full medication list with a healthcare professional and pharmacist before starting.

7) Does Contrave increase blood pressure?

Contrave may increase blood pressure and/or heart rate in some people. If you have high blood pressure or cardiovascular risk factors, your clinician may monitor more closely.

8) Who should not take Contrave?

Certain medical conditions and medicine combinations can make Contrave unsuitable. People with higher seizure risk, certain liver problems, opioid dependence/active opioid use, or other specific contraindications may need different treatment. Your healthcare professional will determine suitability.

9) Can I take Contrave if I work nights or shift work?

Shift patterns can make insomnia more likely. Discuss your schedule with your healthcare professional so dosing can be timed to reduce sleep disruption.

10) Are there lifestyle strategies that improve results?

Yes. Contrave generally performs best alongside:

• A consistent calorie-reduction approach
• Regular activity you can sustain
• Sleep and stress management
• Specific plans for cravings (e.g., planned snacks, delay strategies, replacing habits)

Need more help? If you’re considering Contrave, speak with a healthcare professional for personalised advice based on your health history and current medicines. For any urgent concerns or serious side effects, seek immediate medical attention.