In order to decide whether to perform acute or chronic administration of your drug, along with which time points should be tested, you need to do some research about the actions of your drug. What is the half-life? Some drugs have relatively short duration of action, while some can exert their effects for hours, days or sometimes weeks. Does the drug have any acute effects or does it rely on genomic mechanisms for its actions? Drugs that have only acute effects would require more acute testing time points. Drugs that induce genomic effects may require more chronic administration and daily or weekly time points. Depending on your drug, you may also have to consider pre-treating with your drug before chronic pain develops, depending on its mechanism of action. In any case, route of administration, acute or chronic administration, and times at which to test vary by drug, pain model, species, and purpose, etc. More information is needed.
I fully agree with Renee Donahue, you have to adapt your treatment to your drug. The only advice, I could provide is that for a daily treatment to test your animals before the injection except if the drugs is apply via food or drug.
The drug was tested in models of acute pain and result in nice analgesic effect using single dose (ip) before pain stimuli. I first will look for acute effect of this same drug in model of chronic pain. So I will perform the single injection and observe the animals pain condiction for 6 hours after treatment.
With the results I'll see the chronic administration too.
I agree with Marcus- as self efficacy and functional assessments seen critical in managing humans with chronic pain. How to instill and measure self efficacy in animals is interesting but beyond my area of expertise.
An interesting possible model for 'self-efficacy' in rodents could be burrowing - http://www.ncbi.nlm.nih.gov/pubmed/22396078 - and I would add that including a behavioural outcome, such as burrowing, open field, elevated plus maze, light-dark box etc would add a further dimension to your assessment of analgesic effect.
I treated my animals with the test substance and evaluated it 1-24h after the administration. It work nicely with maximum effect in 6h after i.p. injection.