Suboxone’s most common side effects are headache, insomnia, constipation, nausea, and abdominal pain, each affecting more than 1 in 10 people in clinical trials. Beyond those frequent effects, the medication carries risks that range from dental problems to hormonal changes, especially with long-term use. Most side effects are manageable, but some require attention.
How Suboxone Works in Your Body
Suboxone combines two ingredients: buprenorphine and naloxone. Buprenorphine is a partial opioid, meaning it activates opioid receptors in the brain but produces a much weaker effect than full opioids like heroin or oxycodone. This partial activation is enough to reduce cravings and prevent withdrawal, but it has a built-in ceiling that limits how much euphoria or respiratory slowdown it can cause. Buprenorphine also binds to opioid receptors about 10 times more tightly than naloxone does, so when you take the tablet or film under your tongue as directed, buprenorphine’s effects dominate.
Naloxone is there as a safeguard against misuse. When absorbed through the mouth, naloxone has very low bioavailability (under 10%), so it barely enters your system. But if someone crushes the tablet and injects it, naloxone floods the bloodstream and blocks the opioid receptors, triggering immediate withdrawal. This design is meant to discourage diversion.
Common Side Effects
In pivotal clinical trials involving 472 patients, nearly 73% reported at least one side effect. The most frequent ones overlap with opioid withdrawal symptoms, which makes sense given that many people start Suboxone while transitioning off stronger opioids. The side effects that showed up in more than 1 in 10 patients were:
- Insomnia: difficulty falling or staying asleep
- Headache
- Constipation
- Nausea
- Abdominal pain
A second tier of side effects occurred in 1 to 10 out of every 100 patients. These include excessive sweating, dizziness, drowsiness, vomiting, diarrhea, decreased appetite, back pain, muscle aches and spasms, anxiety, depression, decreased sex drive, and erectile dysfunction. Some people also experience a rapid heartbeat, elevated blood pressure, or a rash with itching. Yawning and flu-like symptoms are common as well, particularly in the early weeks of treatment.
Dental Problems
In 2022, the FDA issued a warning after identifying 305 cases of dental problems linked to buprenorphine products that dissolve in the mouth. These included tooth decay, cavities, oral infections, and tooth loss, and they occurred even in patients with no prior dental issues. Of the 131 serious cases, the most common outcome was tooth extraction, reported 71 times. Others needed root canals, dental surgery, crowns, or implants.
The likely culprit is the acidic environment the dissolving medication creates inside your mouth. To reduce the risk, the FDA recommends taking a large sip of water after the medication fully dissolves, gently swishing it around your teeth and gums, and then swallowing. Wait at least one hour before brushing your teeth so your enamel has time to recover. Regular dental checkups are important for anyone on this medication long term.
Precipitated Withdrawal
One of the most unpleasant experiences with Suboxone happens not from taking it too long, but from starting it too soon. Precipitated withdrawal occurs when you take buprenorphine while other opioids are still active in your body. Because buprenorphine binds so tightly to opioid receptors, it physically displaces whatever opioid is already there. If you still have a significant amount of a full opioid on board, this “knocking off” triggers sudden, intense withdrawal symptoms: sweating, cramping, diarrhea, anxiety, agitation, and nausea, all hitting within minutes rather than hours.
This is why the standard practice is to wait until you’re already in mild to moderate withdrawal before taking your first dose. The timing depends on which opioid you were using and how long it stays in your system.
Dangerous Interactions With Alcohol and Sedatives
The most serious risk with Suboxone isn’t the drug alone. It’s what happens when you combine it with alcohol, benzodiazepines, or other sedatives. Each of these substances suppresses breathing through a different pathway in the brain: opioids work through one receptor system, benzodiazepines through another, and alcohol through yet another. When combined, their effects are not just additive but potentially synergistic, meaning the combined suppression of breathing can be far greater than what either substance would cause on its own.
Buprenorphine combined with alcohol can cause dangerously low blood pressure, profound sedation, respiratory depression, and coma. Post-mortem studies have found that alcohol lowers the threshold at which buprenorphine levels become fatal in accidental overdose cases. While buprenorphine’s ceiling effect offers some protection compared to full opioids, that safety margin narrows significantly when sedatives enter the picture.
Effects on Mood and Mental Health
Suboxone can affect your emotional landscape in ways that aren’t always easy to pin down, since the medication is typically started during a period of major life upheaval. In clinical trials, anxiety, depression, and difficulty concentrating were reported as common side effects (affecting 1 to 10 in 100 patients). Some people describe a kind of emotional flatness or blunting, where strong feelings, both positive and negative, feel muted.
These psychological effects can be hard to separate from the recovery process itself. Someone transitioning off opioids is already dealing with disrupted brain chemistry, sleep changes, and the stress of early recovery. Still, if you notice worsening mood, persistent irritability, or new anxiety that wasn’t present before, it’s worth bringing up with your prescriber. Adjusting the dose sometimes helps.
Hormonal and Sexual Side Effects
Long-term opioid use, including buprenorphine, can interfere with your body’s hormone production. Buprenorphine has less impact on testosterone levels and sexual desire than methadone, but case reports have linked it to low testosterone (hypogonadism), reduced bone density, and sexual dysfunction in men. Interestingly, two studies found no direct correlation between testosterone levels and either the dose or how long someone had been taking buprenorphine, suggesting the sexual side effects may involve mechanisms beyond simple hormone suppression.
Elevated rates of sexual dysfunction have been reported with buprenorphine overall, affecting both desire and function. For those experiencing clinically low testosterone, supplementation is possible but comes with its own trade-offs, including increased impulsivity, mood changes, and the risk of suppressing your body’s natural testosterone production further.
Liver Health
Suboxone’s prescribing information recommends liver function testing before starting treatment and periodic monitoring throughout. Cases of liver injury have been reported, particularly in people who already have hepatitis or other liver conditions. The risk appears to be higher at higher doses and in people with pre-existing liver compromise. Symptoms to watch for include yellowing of the skin or eyes, dark urine, light-colored stools, or persistent upper abdominal pain.
Side Effects During Pregnancy
For pregnant women with opioid use disorder, buprenorphine is generally considered a safer option than methadone, though neither is risk-free for the baby. Neonatal abstinence syndrome, a set of withdrawal symptoms in newborns, occurred in 52% of infants exposed to buprenorphine in the 30 days before delivery, compared to 69% for methadone. When it did occur, babies exposed to buprenorphine needed significantly less treatment and had milder symptoms, including less fussiness, fewer sleep problems, and less vomiting. The decision to use Suboxone during pregnancy involves weighing these risks against the much greater danger of untreated opioid use disorder.