Title: Treatment regimens
Course: Communicable Diseases Part 2 - Ethiopia (Full)

Treatment regimens

According to WHO recommendations and the national guidelines that apply in Ethiopia, the following treatment regimens should be used:

- Note that the number before the bracket refers to the number of months the drug is taken.
Category I and III patients are treated in the intensive phase with combinations of four 'first-line' drugs: isoniazid, rifampicin, pyrazinamide and ethambutol for two months, which can be summarised as 2 (HRZE). In the continuation phase, they receive either a combination of isoniazid and rifampicin for four months 4 (HR), or a combination of isoniazid and ethambutol for six months 6 (HE).
- For Category I patients with a smear-positive sputum result after two months of intensive treatment, extend the intensive phase for an additional one month. Then follow the continuation phase as above. If a patient is still smear-positive after five months of treatment, then they need to be categorised as 'treatment failure' and restart treatment (Category II).
- Category II patients are treated with five drugs for the initial two months of the intensive phase: a combination of isoniazid, rifampicin, pyrazinamide and ethambutol 2 (HRZE), plus streptomycin (S); then continue with four drugs, excluding streptomycin, for an additional one month; then followed by five months of the continuation phase with isoniazid, rifampicin 5 (HR), and ethambutol (E).
- Category IV patients are treated with 'second-line' anti-TB drugs, which you do not need to know the details of.

These different treatment regimens are summarised in Table 14.3.

Table 14.3 Recommended treatment regimens for each treatment category.

Treatment category | TB treatment regimen
Intensive phase (daily or three times every week) | Continuation phase (daily or three times every week)
I | 2 (HRZE) | 4 (HR) or 6 (HE)
II | 2 (HRZES) followed by 1 (HRZE) | 5 (HRE)
III | 2 (HRZE) | 4 (HR) or 6 (HE)
IV | Second-line drugs | Second-line drugs

Knowing this information will enable you to understand the type of drug regimen prescribed by the doctor or clinician for different patient categories. This will help you ensure that the drug treatment is being followed correctly.

Tables 14.4 and 14.5 show the amounts of the different drugs to be administered to patients — in particular the number of tablets they take at any one time. The number of tablets depends upon the body weight of the patient. You are not expected to know the precise dosage of each drug — for example how many milligrams of isoniazid is taken when the patient takes their tablets — but it is very important for you to know the number of tablets a particular patient should be taking. So it is important to check the weight of your patients periodically and refer them to a clinician for an adjustment of drug dose if there is change in their body weight during treatment.

Table 14.4 Drug dosage of Category I and III regimens: (2 HRZE) followed by (6 HE).

Regimen | Intensive phase (2 months) | Continuation phase (6 months)
2 (HRZE) daily | 6 (HE) daily
H 75 mg + R 150 mg + Z 400 mg + E 275 mg tablets | H 150 mg + E 400 mg tablets
Patient's weight | Number of tablets | Number of tablets
20–29 kg | 1½ | 1
30–39 kg | 2 | 1½
40–54 kg | 3 | 2
55–70 kg | 4 | 3
Over 70 kg | 5 | 3

Table 14.4 shows the 2 (HRZE) and 6 (HE) drug regimen for categories I and III. The Ethiopian Federal Ministry of Health have now approved a move to the adoption of 4 (HR) in the continuation phase in such cases, which means four months of isoniazid and rifampicin. It may be some time before 4 (HR) becomes the standard in such cases, so in Table 14.3 both 6 (HE) and 4 (HR) are shown.

Table 14.5 Dosage for Category II regimen: 2 (HRZES), then 1 (HRZE), then 5 (HRE)

Regimen | Intensive phase (3 months) | Continuation phase (5 months)
2 (HRZES) then 1(HRZE) daily | 5 (HRE) (three times per week)
H 75 mg + R 150 mg + Z 400 mg + E 275 mg tablets | S (vials) 1 g intramuscular | H 75 mg + R 150 mg + E 400 mg tablets
Patient's weight (kg) | Number of tablets | Number of vials | Number of tablets
20–29 kg | 1½ | ½ | 1½ + 1
30–39 kg | 2 | ½ | 2 + 1½
40–54 kg | 3 | ¾ | 3 + 2
55–70 kg | 4 | 1 | 4 + 3
Over 70 kg | 5 | 1 | 5 + 3

What is the regimen prescribed for the Category II relapsed TB patient?

Show answer

The drug regimen used for Category II is 2 (HRZES), then 1 (HRZE), then 5 (HRE). Because the intensive phase is three months, but streptomycin is used for only two months (56 doses), it is helpful to write a reminder on the card about when to stop streptomycin.