There are certain factors, which basically influence, how long Valium remains inside body. Those factors are:
- Amount of Valium taken;
- Body fat content;
- Liver and kidney health conditions;
- Presence of other drugs in the system;
- Metabolism rate;
- Method of ingestion.
On average, the basic saliva test can detect the presences of Valium or its metabolites for 7-9 days since the last dose was taken. Blood tests are deemed to be similarly effective, but are more representative for those patients, who take Valium for a long term. Generally, urine tests are the most common drug tests, because they can detect Valium metabolites for a several weeks after the last dose was taken. Hair follicle tests can detect Valium presence up to 90 days after the last dose intake, even though this kind of test is considered to be less reliable comparing to others.
The initial distribution phase of Valium is followed by a prolonged terminal elimination phase with half-life up to 48 hours. The terminal elimination half-life of the active metabolite N-desmethyldiazepam can reach up to 100 hours. Generally, Diazepam (Valium) and its metabolites are excreted in the urine, as their glucuronide conjugates predominantly. Hence, the clearance of diazepam is 20 to 30 mL/min among young adults. Diazepam accumulates upon multiple doses intake and there is some evidence showing that the terminal elimination half-life is slightly prolonged.
Upon oral administration, more than 90% of Diazepam is absorbed. The average time to reach peak plasma concentrations is 1 – 1.5 hours with a range of additional 0.25 – 2.5 hours. Absorption can be delayed and decreased if Valium is administered with a moderate fat meal. Mean lag time in the presence of food is approximately 45 minutes, comparing with 15 minutes when fasting. An increase in the average time to reach peak concentrations to about 2.5 hours can also be observed when the food is in the system, comparing with 1.25 hours when fasting.
Valium presence can be revealed with help urine-based tests. Drug tests or drug panels (if one or more drugs is tested) can indicate if one or more prescription, otherwise illegal drugs are contained in urine. These tests are typically carried out in a usual basis, since they are not intrusive and cheap, as well as fast in terms of administration. The following types of tests can detect the drug presence:
The test is usually carried out in two steps: first, when administrators can facilitate a quick at-home drug test; second, if based on the test, the drugs are present in the body, a sample will be sent to a laboratory for further additional tests. Drug panels are also known as qualitative tests. They are basically used to check, if a particular drug is contained in the urine, but cannot determine its percentage.