Gamma-hydroxybutyrate (ghb) - Phentermine, Topiramate Interaction Details

There are multiple interactions reported between these two agents.

Interaction Details

Phentermine, Topiramate is classified as belonging to the following category: Cns Depressants

GHB may increase the risk of serious CNS and respiratory depression.
Concomitant use of GHB with CNS depressants may increase the risk of serious CNS and respiratory depression.

Interaction Rating

Major

Likelihood of Occurrence

Probable

Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.

References

Product information for Xyrem. Jazz Pharmaceuticals, Inc. Palo Alto, CA. March 2022.

Interaction Details

Phentermine, Topiramate is classified as belonging to the following category: Anticonvulsants

Theoretically, GHB may reduce the effects of anticonvulsant medications.
GHB has been reported to cause seizures, and may theoretically reduce the effectiveness of anticonvulsants. Also, concomitant use of GHB with sedative anticonvulsants may increase the risk of serious CNS and respiratory depression.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

Anon. Multistate outbreak of poisonings associated with illicit use of gamma hydroxy butyrate. JAMA 1991;265:447-8.
Stomberg MW, Knudsen K, Stomberg H, Skärsäter I. Symptoms and signs in interpreting gamma-hydroxybutyrate (GHB) intoxication - an explorative study. Scand J Trauma Resusc Emerg Med. 2014 Apr 23;22:27.
Product information for Xyrem. Jazz Pharmaceuticals, Inc. Palo Alto, CA. March 2022.

Interaction Details

Phentermine, Topiramate is classified as belonging to the following category: Topiramate (Topamax)

Topiramate might increase the levels and clinical effects of GHB.
Concomitant use of GHB with topiramate might increase the blood levels and adverse effects of GHB. In one case report, a female regularly taking prescription GHB (sodium oxybate, Xyrem) 4.5 grams twice nightly for nocturnal headaches and insomnia experienced a worsening cluster headache requiring hospitalization after initiating treatment with topiramate 25 mg, 5 hours prior to the GHB dose. Symptoms included confusion, muscle jerking, miosis, and coma, with recovery within a few hours. Plasma levels of GHB were 2.5-fold higher than when GHB was given alone. Potential mechanisms might include decreased GHB breakdown, increased absorption, and/or increased activity.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

Weiss T, Müller D, Marti I, Happold C, Russmann S. Gamma-hydroxybutyrate (GHB) and topiramate--clinically relevant drug interaction suggested by a case of coma and increased plasma GHB concentration. Eur J Clin Pharmacol. 2013 May;69(5):1193-4.

Gamma-hydroxybutyrate (ghb) - More Interactions

Gamma-hydroxybutyrate (ghb) interacts with 272 drugs

Interaction Rating Key

These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.

Major	The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur.
Moderate	Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur.
Minor	Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction.
Unknown	No interactions have been reported or no interaction data is currently available.