Can I take Clindamycin 3 times 600 times and work in a field on a construction site at a height?

The ability of you to perform work while taking the antibiotic - clindamycin, strictly depends on the reason for which you take this preparation, its tolerance and your state of health. If you suffer from an infection that worsens your psychophysical fitness, if you have symptoms that impair concentration and physical performance, or if after the drug there are any side effects that may affect the ability to perform work safely - then you should withdraw from it so as not to cause an accident and not to bring a threat to yourself and co-workers. Because your question cannot be answered by a pharmacist only on the basis of a post on the forum - if you are not sure, it is best to consult the doctor who ordered your medicine or an occupational medicine doctor.