The therapeutic benefit of temozolomide depends on its ability to alkylate/methylate DNA, which most often occurs at the N-7 or O-6 positions of guanine residues. This methylation damages the DNA and triggers the death of tumor cells. However, some tumor cells are able to repair this type of DNA damage, and therefore diminish the therapeutic efficacy of temozolomide, by expressing a protein O⁶-alkylguanine DNA alkyltransferase (AGT) encoded in humans by the O-6-methylguanine-DNA methyltransferase (MGMT) gene. In some tumors, epigenetic silencing of the MGMT gene prevents the synthesis of this enzyme, and as a consequence such tumors are more sensitive to killing by temozolomide. Conversely, the presence of AGT protein in brain tumors predicts poor response to temozolomide and these patients receive little benefit from chemotherapy with temozolomide.

Usual Adult Dose for Anaplastic Astrocytoma

Oral:
Initial Dose: 150 mg/m2 orally once a day
Maintenance Dose: 200 mg/m2 orally once a day

Duration of Therapy: 5 consecutive days per 28-day treatment cycle

IV:
Initial Dose: 150 mg/m2 IV over 90 minutes once a day
Maintenance Dose: 200 mg/m2 IV over 90 minutes once a day

Duration of Therapy: 5 consecutive days per 28-day treatment cycle

Comments:
-Dose should only be increased to 200 mg/m2 if both the nadir and day of dosing (Day 29, Day 1 of next cycle), the ANC is greater than or equal to 1.5 x 10(9)/L and platelet count is greater than or equal to 100 x 10(9)/L.
-A complete blood count should be obtained on day 22 or within 48 hours of that day of each cycle and weekly until the ANC is above 1.5 x 10(9)/L and the platelet count is above 100 x 10(9)/L.
-The next cycle should not be started until the ANC and platelet count exceed the above levels.
-In clinical trial, treatment could be continued for a maximum of 2 years. Optimum duration of therapy is not known.
-Treatment with this drug may be continued until disease progression.

Use:
-Refractory anaplastic astrocytoma with disease progression on a drug regimen containing nitrosourea and procarbazine.

There are some side-effects of this drug Temozolomide, if you feel too much uncomfortable then see your doctor immediately:

• Insomnia
• Vomiting
• Diarrhoea
• Nausea
• Hives
• Anxiety
• Rash
• Dry skin
• Mouth sores
• Night sweats
• Teary eyes
• Weakness
• Tiredness

Erlotinib hydrochloride (trade name Tarceva) is a drug used to treat non-small cell lung cancer (NSCLC), pancreatic cancer and several other types of cancer. It is a receptor tyrosine kinase inhibitor, which acts on the epidermal growth factor receptor (EGFR).

Treating certain types of advanced or metastatic lung cancer. It is also used to treat certain types of pancreatic cancer in combination with another medicine (gemcitabine).

Erlotinib is a tyrosine kinase inhibitor. It works by helping to stop cancer cells from growing.

Usual Adult Dose for Non-Small Cell Lung Cancer

150 mg orally once a day

Duration of therapy: Until disease progression or unacceptable toxicity

Comments:
-There is no evidence that treatment beyond disease progression is beneficial.

Uses:
-First-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations.
-Maintenance treatment of patients with locally advanced or metastatic NSCLC whose disease has not progressed after four cycles of platinum-based first-line chemotherapy.
-Treatment of locally advanced or metastatic NSCLC after failure of at least one prior chemotherapy regimen.

Gefitinib (ZD1839) (INN, /ɡɛˈfɪtᵻnɪb/, trade name Iressa) is a drug used for certain breast, lung and other cancers.

Gefitinib is the first selective inhibitor of epidermal growth factor receptor’s (EGFR) tyrosine kinase domain. Thus gefitinib is an EGFR inhibitor. The target protein (EGFR) is a member of a family of receptors (ErbB) which includes Her1(erb-B1), Her2(erb-B2), Her3(erb-B3) and Her4 (Erb-B4). EGFR is overexpressed in the cells of certain types of human carcinomas – for example in lung and breast cancers. This leads to inappropriate activation of the anti-apoptotic Ras signalling cascade, eventually leading to uncontrolled cell proliferation. Research on gefitinib-sensitive non-small cell lung cancers has shown that a mutation in the EGFR tyrosine kinase domain is responsible for activating anti-apoptotic pathways. These mutations tend to confer increased sensitivity to tyrosine kinase inhibitors such as gefitinib and erlotinib. Of the types of non-small cell lung cancer histologies, adenocarcinoma is the type that most often harbors these mutations. These mutations are more commonly seen in Asians, women, and non-smokers (who also tend to more often have adenocarcinoma).

Gefitinib inhibits EGFR tyrosine kinase by binding to the adenosine triphosphate (ATP)-binding site of the enzyme. Thus the function of the EGFR tyrosine kinase in activating the anti-apoptotic Ras signal transduction cascade is inhibited, and malignant cells are inhibited.

Usual Adult Dose for Non-Small Cell Lung Cancer

250 mg orally once a day

Duration of therapy: Until disease progression or unacceptable toxicity

Comments:
-Information on FDA-approved tests for detection of EGFR mutations in NSCLC: http://www.fda.gov/CompanionDiagnostics

Use: First-line treatment of metastatic non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations as detected by an FDA-approved test.

Gefitinib may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• dry skin
• itching
• rash
• acne
• mouth sores
• weakness

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

• new or worsening shortness of breath, cough, or fever
• severe or ongoing diarrhea
• severe abdominal pain
• loss of appetite
• eye pain, redness, or irritation
• vision changes
• watery eyes
• eye sensitivity to light
• hives
• blisters or peeling skin
• swelling of the eyes, face, lips, tongue, throat, hands, arms, feet, ankles or lower legs
• nausea
• vomiting
• yellowing of the skin or eyes
• dark urine
• pale stools
• pain or discomfort in the right upper stomach area

Gefitinib may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Ampicillin is an antibiotic used to prevent and treat a number of bacterial infections, such as respiratory tract infections, urinary tract infections, meningitis, salmonellosis, and endocarditis. It may also be used to prevent group B streptococcal infection in newborns. It is used by mouth, by injection into a muscle, or intravenously. Like all antibiotics, it is not useful for the treatment of viral infections.

Common side effects include rash, nausea, and diarrhea. It should not be used in people who are allergic to penicillin. Serious side effects may include Clostridium difficile colitis or anaphylaxis. While usable in those with kidney problems, the dose may need to be decreased. Its use during pregnancy and breastfeeding appears to be generally safe.

Ampicillin is a penicillin antibiotic. It works by killing sensitive bacteria by interfering with formation of the bacteria’s cell wall while it is growing. This weakens the cell wall and it ruptures, resulting in the death of the bacteria.

Usual Adult Dose for Bacterial Infection

The manufacturer recommends:
Parenteral:
-Infections of the respiratory tract and soft tissues: 250 to 500 mg IM or IV every 6 hours
-Infections of the gastrointestinal and genitourinary tracts (including Neisseria gonorrhoeae infections in females): 500 mg IM or IV every 6 hours
-Urethritis in males due to N gonorrhoeae: 500 mg IM or IV every 8 to 12 hours for 2 doses
-Bacterial meningitis: 150 to 200 mg/kg/day in equally divided doses every 3 to 4 hours; may start with IV drip therapy and continue with IM injections
-Septicemia: 150 to 200 mg/kg/day; start with IV administration for at least 3 days and continue with IM route every 3 to 4 hours

Usual used for:

• Bacterial Infection
• Endocarditis
• Bacterial Endocarditis Prophylaxis
• Meningitis
• Septicemia
• Gastroenteritis
• Intraabdominal Infection
• Skin or Soft Tissue Infection
• Pharyngitis
• Sinusitis
• Upper Respiratory Tract Infection
• Pneumonia
• Bronchitis
• Urinary Tract Infection
• Pyelonephritis
• Shigellosis
• Typhoid Fever
• Prevention of Perinatal Group B Streptococcal Disease
• Surgical Prophylaxis
• Leptospirosis
• Peritonitis
• Otitis Media

MORE COMMON SIDE EFFECTS

• nausea
• vomiting
• diarrhea
• rash