Phentermine Interactions
Showing entire list of all interactions, including brand names and combination drugs.
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Medications known to interact with phentermine
O
- Obezine (phendimetrazine)
- Octocaine 100 (epinephrine / lidocaine)
- olodaterol
- olodaterol / tiotropium
- Omnihist II LA (chlorpheniramine / methscopolamine / phenylephrine)
- Omnihist L.A. (chlorpheniramine / methscopolamine / phenylephrine)
- Omnipaque 12 (iohexol)
- Omnipaque 140 (iohexol)
- Omnipaque 180 (iohexol)
- Omnipaque 180 Redi-Unit (iohexol)
- Omnipaque 210 (iohexol)
- Omnipaque 240 (iohexol)
- Omnipaque 240 Redi-Unit (iohexol)
- Omnipaque 300 (iohexol)
- Omnipaque 350 (iohexol)
- Omnipaque 9 (iohexol)
- Omnipaque Flexipak (iohexol)
- Onglyza (saxagliptin)
- Onset Forte (acetaminophen / chlorpheniramine / phenylephrine)
- Onsolis (fentanyl)
- Onzetra Xsail (sumatriptan)
- Or-Phen-Ade (chlorpheniramine / phenylpropanolamine)
- Orabloc (articaine / epinephrine)
- Oraltag (iohexol)
- Oratuss 12 (carbetapentane / guaifenesin / phenylephrine)
- Orbivan (acetaminophen / butalbital / caffeine)
- Ordrine (chlorpheniramine / phenylpropanolamine)
- Ordrine AT (caramiphen / phenylpropanolamine)
- Oreticyl 25 (deserpidine / hydrochlorothiazide)
- Oreticyl 50 (deserpidine / hydrochlorothiazide)
- Oreticyl Forte (deserpidine / hydrochlorothiazide)
- Orinase (tolbutamide)
- Orlenta (chlorpheniramine / pseudoephedrine)
- Ormazine (chlorpromazine)
- Ornade Spansules (chlorpheniramine / phenylpropanolamine)
- Ornex (acetaminophen / pseudoephedrine)
- Ornex Maximum Strength (acetaminophen / pseudoephedrine)
- Oroxine (levothyroxine)
- Orphengesic (aspirin / caffeine / orphenadrine)
- Orphengesic Forte (aspirin / caffeine / orphenadrine)
- Orvaten (midodrine)
- Oseni (alogliptin / pioglitazone)
- OsmoPrep (sodium biphosphate / sodium phosphate)
- Overtime (caffeine)
- ozanimod
- Ozempic (semaglutide)
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Drug Interaction Classification
| Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
| Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
| Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
| No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.