Chart 6. Adverse reactions and approach.a .
| Adverse reactions | Probable causative drug | Approach |
|---|---|---|
| Minor | ||
| Anorexia, vomiting, nausea, abdominal pain | R, H, Z | Advise patients to take the antituberculosis drugs at the appropriate time, prescribe symptomatic treatment, and reassess the need for requesting the determination of hepatic enzyme levels. |
| Orange- or red-colored sweat/urine | R | Instruct patients. |
| Pruritus | S, R | Prescribe antihistamines. |
| Joint pain | Z | Prescribe aspirin. |
| Paresthesia | H (common) or E (uncommon) | Prescribe pyridoxine (50 mg/day). |
| Asymptomatic hyperuricemia | Z | Prescribe follow-up/diet. |
| Hyperuricemia and arthralgia | E | Prescribe follow-up/diet/symptomatic treatment. |
| Arthritis/arthralgia | H, Z | Prescribe symptomatic treatment. |
| Headache, anxiety, euphoria, insomnia | H | Instruct patients. |
| Major | ||
| Exanthema/pruritus | S, R | Discontinue the drugs and reintroduce one drug at a time. |
| Fever, oliguria, exanthema (interstitial nephritis, rhabdomyolysis) | Z | Discontinue Z. Use the 2RHE/7RH regimen. |
| Hypoacusis | S | Replace S with E (maintain the planned duration of the regimen). |
| Vertigo/nystagmus | S | Replace S with E (maintain the planned duration of the regimen). |
| Convulsive seizures, encephalopathy | H | Use the 2RZES5/7RE regimen. |
| Vomiting and mental confusion (prehepatic jaundice?) | Any drug (H, R, Z, E, S, Et) | Discontinue the regimen and request the determination of hepatic enzyme levels. If ALT is abnormal, follow a regimen for managing hepatotocixity.b |
| Jaundice (if other causes have been ruled out) | Any drug (H, R, Z, E, S, Et) | Discontinue the regimen and request the determination of hepatic enzyme levels. If ALT is abnormal, follow a regimen for managing hepatotoxicity.b |
| Optic neuritis (loss of side vision, change in color vision) | E (common) and H (uncommon) | Use the 2RHZ/4RH or 2RZES5/7RE regimen. |
| Shock, purpura | R | Use the 2HZES5/10HE regimen. |
Adapted from Conde et al., 24 Maciel et al., 32 and Ferreira et al. 33 ) R: rifampin; H: isoniazid; Z: pyrazinamide; E: ethambutol; S: streptomycin; Et: ethionamide; and ALT: alanine aminotransferase. aThe number preceding the acronym indicates duration of treatment in weeks. The subscript number after a drug abbreviation indicates the number of days per week that the drug should be used; if there is no subscript number, treatment with that drug is daily. bSee “Tuberculosis and liver disease.”