The drugs should be given in this order:

Day 1: INH at 1/3 or 1/4 dose
Day 2: INH at 1/2 dose
Day 3: INH at full dose
Day 4: RMP at 1/3 or 1/4 dose
Day 5: RMP at 1/2 dose
Day 6: RMP at full dose
Day 7: EMB at 1/3 or 1/4 dose
Day 8: EMB at 1/2 dose
Day 9: EMB at full doseNo more than one test dose per day should be given, and all other drugs should be stopped while test dosing is being done. So on day 4, for example, the patient only receives RMP and no other drugs are given. If the patient completes the nine days of test dosing, then it is reasonable to assume that PZA has caused the hepatitis and no PZA test dosing need be done. The reason for using the order for testing drugs is because the two most important drugs for treating TB are INH and RMP, so these are tested first: PZA is the most likely drug to cause hepatitis and is also the drug that can be most easily omitted. EMB is useful when the sensitivity pattern of the TB organism are not known and can be omitted if the organism is known to be sensitive to INH. Regimens omitting each of the standard drugs are listed below. The order in which the drugs are tested can be varied according to the following considerations:

The most useful drugs (INH and RMP) should be tested first, because the absence of these drugs from a treatment regimen severely impairs its efficacy.
Forearm
The median nerve continues in the cubital fossa medial to the brachial artery and passes between the two heads of  the pronator teres, deep to the bicipital aponeurosis (aponeurosis of biceps) and superficial the brachialis muscle. It crosses the ulnar artery (branch of brachial artery) while being separated by the deep head of the pronator teres. It then travels between the flexor digitorum superficialis (above) and flexor digitorum profundus (below). The median nerve is accompanied by the median artery (a branch of anterior interosseous artery) during this course. Then,  about 5 cm above the flexor retinaculum (wrist), it emerges between the flexor digitorum superficialis (medially) and the flexor carpi radialis (laterally) into the hand.The main trunk of the median nerve innervates the superficial and deep groups of the muscles in the anterior compartment of the forearm with the exception of flexor carpi ulnaris. The median nerve does this by giving off two branches as it courses through the forearm:

Muscular branches are given off in the cubital fossa to supply flexor carpi radialis, palmaris longus, and flexor digitorum superficialis. The anterior interosseous branch is given off in the upper part of the forearm, courses with the anterior interosseous artery and innervates flexor pollicis longus and the lateral half of flexor digitorum profundus (the ulnar half is supplied by ulnar nerve, as is the flexor carpi ulnaris muscle). It ends with its innervation of pronator quadratus.