Dr. Mary Galloway • Newberg, Oregon

Drug-Nutrient Interactions

  • Posted on May 1, 2017

Natural does not mean Harmless. Poison ivy is natural but I would not eat it! Supplements can interact with prescription drugs, so it is important to know these interactions before taking them together. Let’s look at the top 10 prescription drugs in the US and the supplements that may interact with them. Synthroid (levothyroxine).
This is a synthetic thyroid medication. Oral supplements containing calcium, iron, rose hips or caffeine can reduce the absorption of Synthroid. Take them 2 hours away from Synthroid.

Crestor (rosuvastatin).
This is popular cholesterol-reducing medication. Do not take red yeast rice supplements as they can increase the toxicity of this drug. Niacin (Vitamin B3) can increase the toxicity of Crestor if more than 1 gram per day is taken. Calcium supplements should be taken 2 hours away from Crestor because calcium interferes with the absorption of Crestor into the body, making it less effective. Crestor decreases the levels of CoQ10, so more CoQ10 may be needed.

Ventolin HFA (albuterol).
This is an inhaled asthma medication. Caffeine and green tea can increase the stimulant effect of this drug. Melatonin is a sedative while Ventolin is a stimulant, so they may interfere with each other. Do not take these supplements unless approved by your doctor.

Nexium (esomeprazole).
This “purple pill” is for ulcers, heartburn and esophageal reflux. Nexium can interfere with the effectiveness of oral iron or rose hips supplements. St. John’s Wort or Devil’s Claw supplements can decrease the effectiveness of Nexium. Do not take any of these supplements unless approved by your doctor.

Advair (fluticasone).
This is an inhaled asthma medication. Caffeine and Green Tea can increase the stimulant effect of this drug. Grapefruit or Grapefruit Juice increase the effect of Advair. Melatonin is a sedative while Ventolin is a stimulant, so they may interfere with each other. Do not take these supplements unless approved by your doctor.

Lantus (insulin glargine).
This is a long-lasting injectable medication used to control blood sugar in diabetics. Bitter Melon or Cinnamon supplements can increase the effect of Lantus, possibly resulting in hypoglycemia (low blood sugar). Chromium, CoQ10, Devil’s Claw, Elderberry, Eucalyptus, Gotu Kola, Gymnema, Maitake Mushroom, Nettle, Panax Ginseng or Siberian Ginseng (Eleutherococcus) supplements can increase the effect of Lantus to a lesser degree. Do not take these supplements unless approved by your doctor.

Vyvanse (lisdexamfetamine).
This medication is used to treat ADHD with hyperactivity. Caffeine supplements can increase Vyvanse’s effects. Calcium Carbonate or Magnesium Oxide supplements may increase the activity of this drug by keeping it in the body longer. Green Tea supplements may increase the effect of Vyvanse. Melatonin, Motherwort, Skullcap or Shepherd’s Purse supplements may increase sleepiness while Vyvanse decreases it, so it is not known how they may act together. Yohimbine supplements can increase the effects of Vyvanse. American Ginseng supplements may increase the effects of Vyvanse to a lesser degree. Eucalyptus or Sage supplements may reduce the effectiveness of Vyvanse. Guarana and Yerba Mate supplements may increase the effects of Vyvanse. Do not take these supplements unless approved by your doctor.

Lyrica (pregabalin).
This prescription drug is for fibromyalgia or neuropathic pain. According to Medscape.com, there are no supplements that interact with this medication.

Spiriva (tiotopium).
This is an inhaled medication for COPD. This medication does not work well with supplements containing Huperzine A. Do not take this supplement unless approved by your doctor.

Januvia (sitagliptin).
This medication is for controlling Type II Diabetes. Bitter Melon, Cinnamon or Shark Cartilage supplements increase the effectiveness of Januvia and may cause hypoglycemia (low blood sugar). Agrimony, American Ginseng, Chromium, Damiana, Devil’s Claw, Elderberry, Eucalyptus, Fo-Ti Root, Gotu Kola, Gymnema, Horse Chestnut, Juniper, Maitake Mushroom, Nettle, Sage, Stevia or Vanadium containing supplements can increase the effects of Januvia to a lesser degree. Do not take these supplements unless approved by your doctor.

As you can see, there are many known interactions. If you are on any prescription medication, be sure to check with your doctor or pharmacist to be sure the supplements you want to take are compatible. And keep your doctor informed of any supplements you are taking. If there are any changes to your medical plan, (s)he will make sure they all work together for optimal health.

Reference – Medscape (a division of WebMD), 4/19/17.