Modafinil is a nootropic or cognitive enhancing drug. It improves cognitive functions especially memory, executive function, creativity and motivation. In order to understand how it works, it is crucial to get conversant with how long the effects last.

Understanding drug half-life

Drug half-life is defined as the time taken for amount of that drug in the body to reduce by half. This is mainly affected by body processes involved in excretion of the drug. The half-life does to change with dosage or the duration of time you have been on the medication.

The half-life of a drug matters because it determines the extent of withdrawal symptoms. Those with a short half-life have more withdrawal symptoms upon discontinuation of the drug. Drugs with a long half-life have fewer withdrawal symptoms. Coming off of the later is easier compared to the former.

Half-life is modafinil and its effects

Given that modafinil is meant to promote wakefulness, knowing how long its effects will last is important. Modafinil peak plasma concentration are recorded within 2-3 hours after taking the drug. To understand how long it will last, it is important to understand its enantiomers. The pill has a mixture of R and S enantiomers in the ratio 1:1. the half-life of the R enantiomer is 15 hours while that of the S enantiomer is 4 hours.

The average half-life of the pill is calculated by adding the figures and dividing by two. This will give an average half life of 9.5 hours. However, there are pills which only contain the R enantiomer.

When you know the half-life of the modafinil, you can tell when the effects will start wearing off. After reaching half-life, the drug will no longer have powerful effects on the body systems. To note is that the half-life is not linear in many cases. At times the effects will be sudden.

Effects of taking lower and higher doses

When taken in large doses, it will take a longer time to be cleared completely from the system compared to smaller doses. Even though the half-life is the same, the remaining drug in your body will be more when the dose was larger even after the half-life time. You will be able to go on with your work normally.

When the dosage of modafinil taken was low, you might experience a sudden sleepiness after it has reached its peak concentration in the plasma.

Using this knowledge of the half-life of the drug and the effects of varying does, your doctor will prescribe the right amount depending on the activities you will be taking part in.