Prescribed limits don’t just exist for illegal drugs, they exist for prescription medication too. If a blood reading above the prescribed limit has been provided, the police will charge you with drug driving. If convicted, the minimum disqualification period is 12 months.
If you’re taking medication as prescribed by your doctor, you should be safe to carry on driving as normal.
The government is unable to provide any guidance on what the new drug driving limits actually mean. There are too many variables.
A medical defence is available for those drivers who have been taking medication as directed by their doctor but are found to be over the drug driving limit.
However, the burden to establish this defence is placed upon the defence. This means that we must present some evidence that the drug is being used as advised (such as a prescription, leaflet etc…). Once we have discharged this evidential burden, it then falls on the CPS to disprove our defence ‘beyond all reasonable doubt’.
There is always the possibility that your results are above the limit, despite you taking the ‘correct’ dose of medication.
Any given drug’s presence in your system is often measured by its ‘half-life’. This is the period of time required for the amount of drug in your system to be reduced by one-half. Most drugs, whether illegal or not, will have been completely eliminated after 24 hours. But what if the drug remains in your system for longer than usual, putting you at risk of being caught drug driving?
Urine, like other body fluids, can be either acidic or alkaline. Interestingly, the Ph-level of your urine can affect the length of time is takes to excrete a substance. Alkaline urine can double the amount of time it takes for a drug to leave your system.
What makes my urine alkaline?