Naltrexone/Bupropion

About Naltrexone/Bupropion

Naltrexone is an opioid antagonist; bupropion, the active ingredient of Wellbutrin and Zyban, weakly blocks the reuptake of dopamine and norepinephrine. Laboratory studies suggest the pair act on the brain’s appetite and reward centers, though how it causes weight loss is not fully understood. The label approves it for adults with obesity or overweight in the presence of at least one weight-related condition, not for children, and its effect on heart disease and death has not been established. The dose builds weekly: one tablet each morning in week 1; one in the morning and one in the evening in week 2; two in the morning and one in the evening in week 3; then two tablets twice a day, the maximum. If weight loss after 12 weeks at that dose is less than 5 percent of starting weight, the label says to stop. Moderate or severe kidney impairment, moderate liver impairment and CYP2B6 inhibitors such as clopidogrel limit the dose to one tablet twice a day.

The boxed warning explains that antidepressants raised the risk of suicidal thoughts and behaviors in children, adolescents and young adults in short-term studies, so everyone starting it is watched for worsening mood or new suicidal thoughts; it is not approved for depression. Bupropion can cause seizures, more often at higher doses, so it is not taken with a seizure disorder or past seizures, bulimia or anorexia, or while abruptly stopping alcohol, benzodiazepines, barbiturates or antiseizure drugs, and it is stopped for good after a seizure. It is also ruled out with uncontrolled high blood pressure, regular opioid use or opioid withdrawal, other bupropion products, and MAO inhibitors within 14 days, including linezolid and intravenous methylene blue. Blood pressure and pulse can rise, so they are checked before and during treatment; other warnings cover allergic reactions, liver injury, mania, angle-closure glaucoma and low blood sugar in people on diabetes medicines. Nausea, constipation, headache, vomiting, dizziness, insomnia, dry mouth and diarrhea are the most common side effects.

Because naltrexone blocks opioids, trying to overcome the block with large opioid doses can cause a fatal overdose. People who have been taking opioids need at least 7 to 10 days without them before starting, and up to two weeks after buprenorphine or methadone; if opioid treatment is needed later, Contrave is paused, and after stopping it a person may be more sensitive to opioids than before. Weight loss offers no benefit in pregnancy and may harm the baby, so the label says to stop it once pregnancy is recognized. Bupropion can cause false-positive urine screening tests for amphetamines.

Taking Naltrexone/Bupropion

How to take it

In the morning, and in the evening once the dose builds up; never more than two tablets at one time or four in a day. Swallow tablets whole; do not cut, chew or crush them, and do not take them with a high-fat meal, which raises the amount absorbed and the risk of a seizure.

If you miss a dose

Skip the missed dose and take the next one at its usual time. Do not take extra tablets to make up for it.

Storage

At room temperature, away from excess heat and moisture (not in the bathroom), out of reach of children. Use a take-back program rather than flushing it.

Interactions to know about

Do not take it with opioid medicines or other bupropion products, or within 14 days of an MAO inhibitor. It raises levels of drugs cleared by CYP2D6, such as metoprolol, flecainide and some antidepressants and antipsychotics, and lowers digoxin levels; ritonavir, lopinavir and efavirenz are avoided. Keep alcohol to a minimum or avoid it.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Naltrexone/Bupropion differs from pharmacy to pharmacy

Contrave is sold only as the brand, so quotes differ mainly by each pharmacy’s markup and fees, and a pharmacy that rarely dispenses it may need to order it.

The maintenance dose is four tablets a day, a large monthly count, while the first four weeks need fewer tablets as the dose builds, so a first prescription written for the full quantity can mean paying for tablets that are not needed yet.

Ways to pay less for Naltrexone/Bupropion without insurance

• Ask the maker whether a savings or assistance program applies to someone paying cash; many copay cards require commercial insurance.
• For the first month, ask the prescriber to write a quantity that matches the four-week dose build-up.
• Compare quotes from more than one pharmacy, since a brand price leaves room for different markups.
• At the 12-week check, ask the prescriber whether to continue, and if quotes are high, whether another weight-management medicine with a generic, such as phentermine and topiramate, would suit you.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Naltrexone/Bupropion

1. 1.Is it safe with my antidepressant, heart or blood pressure medicines?
2. 2.What should I do if I need an opioid pain medicine for surgery or an injury?
3. 3.How should I fit my doses around meals, and what counts as a high-fat meal?
4. 4.Which mood changes or other symptoms mean I should call my prescriber?

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