Q. Is it normal to have a drug test threshold 1000 ng/mL for 5 mg of Dextro-amphetamine?

Answered by
Dr. Arul Amuthan L
and medically reviewed by iCliniq medical review team.
This is a premium question & answer published on Dec 12, 2022

Hi doctor,

I take 5 mg of Dextro-amphetamine (low-dose Adderall) daily as prescribed. I have to take a monthly drug test. However, my results consistently show negative for Amphetamines which is a problem because they see I have a prescription for Dextro-amphetamine. Yet, it appears I am doing something else with it since my urinalysis keeps showing negative for Amphetamines. I do not know why my results keep coming back negative. I know I am taking a very low dose, though, and the drug test threshold is 1000 ng/mL. I am currently taking Methadone (55 mg), Wellbutrin (300 mg), and Propanolol (40 mg). Is that too high of a threshold for 5 mg of Dextro-amphetamine?



Welcome to

I understand your concern.

Amphetamine excretion increases with increasing urine flow. Therefore, high urine flow (due to over-drinking water or diuretic drugs) will increase excretion. Hence not detectable in urine. The excretion is also increased with acidic urine pH. If any acidic foods (lemon, orange, vitamin C, etc.) or acidic drugs can hurry up the excretion of Amphetamine, so not be detected in urine. Please think about any such foods you are consuming. The concomitant drugs do not have any of such actions. The earlier research on human volunteers showed that the urine Amphetamine test was positive only in 19 % if the oral dose was 5 mg. As the dose is increased, the detecting ability is increased. Another factor is the screening cutoff of 1000 ng/mL (reference range), which is too high for the low (5 mg) oral dose. The above-said factors contribute to your urine negative test.

I hope you find it helpful.

Kind regards.

Was this answer helpful?


Same symptoms doesn’t mean you have the same problem. Consult a doctor now!

Related Questions:
I took Vicodin. How long will it take to clear from my system?

.. a drug, which is a combination of Acetaminophen and Hydrocodone. Acetaminophen has a half-life of 4 hours and Hydrocodone has a half-life of 4 to 5 hours. So, both drugs combination that is Vicodin can be completely washed out from the body wit...   Read full

Is it a must to stop Adderall while getting anesthesia?

.. need not stop Adderall (combination of Amphetamine and Dextroamphetamine) to get anesthesia.Secondly, the only side effect that may happen is resistant hypotension due to catecholamines depletion. That can be taken care of by the anesthetist.Posto...   Read full

I would like to know the safety of Adderall for ADHD during pregnancy?

I have a history associated with depression, anxiety and ADHD (attention deficit hyperactivity disorder) ...   Read full

Also Read Answers From:

Also Read

Improving the Health and Wellbeing of People Living With Neglected Tropical Diseases
Neglected tropical diseases can be efficiently treated with various cross-sectoral public health interventions to improv...  Read more»
Holi Colors - Are They Safe?
Holi is known as the festival of colors. But are the colors worth playing with? Let us find out.  Read more»
Onions - Nutrition, Health Benefits, and Side Effects
Onions are an imperative ingredient for most of the main course dishes. Read the article below to learn about them more.  Read more»

Ask your health query to a Wellness Expert online?

Ask a Toxicologist Now

* guaranteed answer within 4 hours.

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.