Indications for SIKLOS:

To reduce the frequency of painful crises and to reduce the need for blood transfusions in patients with sickle cell anemia with recurrent moderate to severe painful crises.

Adults and Children:

<2yrs: not established. Base dose on ideal or actual weight, whichever is less. If difficulty swallowing, may disperse tab in teaspoonful of water immediately before use. ≥2yrs: initially 20mg/kg/day as a single dose. May increase dose by 5mg/kg/day every 8 weeks or if painful crisis occurs; give until mild myelosuppression (ANC 2000–4000/uL) is achieved, up to max 35mg/kg/day; increase dose only if blood counts are in an acceptable range; do not increase dose if myelosuppression occurs. If blood counts toxic, discontinue until hematologic recovery, see full labeling for dosage adjustments. Renal impairment (CrCl <60mL/min or ESRD): initially 10mg/kg/day; give dose following dialysis (monitor).

Boxed Warning:

Myelosuppression. Malignancies.

SIKLOS Warnings/Precautions:

Risk of severe myelosuppression. Monitor blood counts at baseline and every 2 weeks during therapy; interrupt or reduce dose if necessary; resume at lower dose. Markedly depressed bone marrow function: do not initiate. Monitor for secondary malignancies. Avoid sun exposure. Macrocytosis may mask folic acid deficiency; prophylactic folic acid is recommended. Myeloproliferative disorders; reduce dose or discontinue if cutaneous vasculitic ulcerations occur. Avoid in those with leg ulcers. Obtain fetal hemoglobin (HbF) levels every 3–4 months; may be used to assess efficacy. Renal or hepatic impairment: monitor closely. Embryo-fetal toxicity. Pregnancy: avoid; exclude status prior to initiation. Advise females with reproductive potential and males (w. female partners) to use effective contraception during and for ≥6 months after therapy. Nursing mothers: not recommended.

SIKLOS Classification:


SIKLOS Interactions:

Avoid concomitant didanosine, with or without stavudine, or other antiretrovirals (may cause pancreatitis [permanently discontinue if occurs], fatal hepatotoxicity, peripheral neuropathy). Avoid live vaccines. Increased risk of vasculitic toxicities with interferon therapy. May cause falsely elevated results in urea, uric acid, and lactic acid assays.

Adverse Reactions:

Infections, leukopenia, thrombocytopenia, anemia, neutropenia, skin and subcutaneous disorders, GI upset, Vit.D deficiency, headache, fever; secondary malignancies, vasculitic toxicities, macrocytosis.


Wear disposable gloves when handling tabs or bottle.

Generic Drug Availability:


How Supplied:

Tabs 100mg—60; 1000mg—30

Pricing for SIKLOS

100mg tablet (Qty: 30)
Appx. price $166