BelviqThis medication acts on serotonin, a neurotransmitter that has been implicated in depression. Since many psychiatric meds also work on the serotonin system, it's not surprising that there's a potential for serious side effects when these medicines are combined.
Serotonin Syndrome and Neuroleptic Malignant Syndrome, both potentially life-threatening conditions, are possible with serotogenic drugs, and thus adding Belviq to existing medications might make this more likely.
The risk and safety of Belviq when used with other drugs that affect serotonin hasn't been evaluated yet, but the label contains a warning to "use extreme caution" when administering Belviq with drugs "including, but not limited to, triptans, monoamine oxidase inhibitors (MAOIs, including linezolid, an antibiotic which is a reversible non-selective MAOI), selective serotonin reuptake inhibitors (SSRIs), selective serotonin-norepinephrine reuptake inhibitors (SNRIs), dextromethorphan, tricyclic antidepressants (TCAs), bupropion, lithium, tramadol, tryptophan, and St. John's Wort."
QsymiaQsymia is a combination of two drugs, phentermine and topiramate. The latter, also sold under the brand name Topamax, is an anti-epilepsy drug sometimes used as a mood stabilizer in bipolar disorder.
For the last few years, the FDA has required all anticonvulsant medications to carry a warning about a potential increase in suicidal ideation. Since Qsymia contains topiramate (which is an anticonvulsant), the official prescribing information for the drug contains this version of the warning:
Qsymia can cause mood disorders, including depression, and anxiety, as well as insomnia. Patients with a history of depression may be at increased risk of recurrent depression or other mood disorders while taking Qsymia. The majority of these mood and sleep disorders resolved spontaneously, or resolved upon discontinuation of dosing.In addition:
For clinically significant or persistent symptoms consider dose reduction or withdrawal of Qsymia. If patients have symptoms of suicidal ideation or behavior, discontinue Qsymia.
Avoid Qsymia in patients with a history of suicidal attempts or active suicidal ideation.
- There may be problems when Qsymia is taken along with benzodiazepines, a type of anti-anxiety and sedative medication, or other sleep medications.
- Qsymia should not be taken during or within 14 days of stopping any MAOI antidepressant.
- Care is needed when taking this drug with an anticonvulsant mood stabilizer, especially carbamazepine and valproate.
The Bottom Line on Belviq, Qsymia and Mood DisordersIt's not impossible for people who have bipolar disorder or major depression to be treated with either of these drugs, but extremely careful monitoring is necessary. Life-threatening side effects are possible. In some cases, regular blood tests are recommended. Work with your doctors closely if either Belviq or Qsymia is prescribed for you, and make sure you tell them about any changes in mood, sleep, anxiety, stress or physical health. Losing weight is not worth the significant health problems that might occur!
US Food and Drug Administration: Approved Label for Belviq. 27 June 2012.
US Food and Drug Administration: Approved Label for Qsymia. 17 July 2012.