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mefloquine hydrochloride

Apo-Mefloquine (CA), Lariam

Pharmacologic class: 4-quinolinemethanol derivative, quinine analog

Therapeutic class: Antimalarial

Pregnancy risk category C


Unknown. Thought to increase intravesicular pH in parasite acid vesicles and form complexes with hemin, inhibiting parasite development.


Tablets: 250 mg

Indications and dosages

Acute malarial infection

Adults: 1,250 mg P.O. as a single dose

Children: 20 to 25 mg/kg P.O. in two divided doses given 6 to 8 hours apart

Malaria prophylaxis

Adults and children weighing more than 45 kg (99 lb): 250 mg P.O. once weekly on same day each week, starting 1 week before entering endemic area and continuing for 4 weeks after leaving area

Children weighing 30 to 45 kg (66 to 99 lb): 187.5 mg P.O. q week

Children weighing 20 to 30 kg (44 to 66 lb): 125 mg P.O. q week

Children weighing 10 to 20 kg (22 to 44 lb): 62.5 mg P.O. q week

Children weighing 5 to 10 kg (11 to 22 lb): 31.25 mg P.O. q week


• Hypersensitivity to drug, related agents (quinine, quinidine), or excipients
• Prophylactic use in patients with active depression, recent history of depression, generalized anxiety disorder, psychosis, schizophrenia, other psychiatric disorders, or history of seizures


Use cautiously in:
• cardiac disorders, seizure disorders
• pregnant or breastfeeding patients
• children.


• Don't give on empty stomach. Administer with at least 240 ml of water.
• Know that after completing mefloquine therapy for acute malarial infection, patient should receive primaquine (or other 8-aminoquinolone) to prevent relapse.

Adverse reactions

CNS: dizziness, syncope, headache, psychotic changes, depression, hallucinations, confusion, anxiety, fatigue, vertigo, seizures

EENT: blurred vision, tinnitus

GI: nausea, vomiting, diarrhea, loose stools, abdominal discomfort, anorexia

Hematologic: leukopenia, thrombocytopenia

Musculoskeletal: myalgia

Skin: rash

Other: fever, chills


Drug-drug.Beta-adrenergic blockers, quinidine, quinine: ECG abnormalities, cardiac arrest

Chloroquine, quinine: increased risk of seizures

Valproic acid: decreased valproic acid blood level, loss of seizure control

Drug-diagnostic tests.Hematocrit, platelets, white blood cells: decreased values

Transaminases: transient increases

Patient monitoring

Monitor patient with acute Plasmodium vivax malaria who is at high risk for relapse. Because drug doesn't eliminate exoerythrocytic (hepaticphase) parasites, patient should receive primaquine after mefloquine therapy.

Watch for psychiatric symptoms, such as acute anxiety, depression, restlessness, or confusion. These may precede more serious psychiatric events.
• Evaluate hepatic function during prolonged prophylactic therapy.

In patients receiving related drugs (such as quinine, quinidine, or chloroquine) concurrently, be alert for ECG abnormalities and seizures. Separate administration times by at least 12 hours.

Closely monitor patients with serious or life-threatening Plasmodium falciparum infection. Be aware that they should receive I.V. antimalarial drugs and that mefloquine may be used to complete course of therapy.

Patient teaching

• Tell patient to take with full glass of water and not on empty stomach.
• In prophylactic use, instruct patient to take first dose 1 week before departure and to continue therapy as prescribed upon return. Tell him to take drug on same day each week.
• Advise patient to report fever after returning from malarious area.
• Inform patient that malaria prophylaxis should include protective clothing, insect repellent, and bed netting.

Tell patient to immediately report psychiatric symptoms (such as acute anxiety, depression, restlessness, or confusion) and to stop taking drug.
• Caution patient to avoid driving and other hazardous activities because drug may cause dizziness.
• Instruct patient to have periodic ophthalmic exams, because drug may cause eye damage.
• Tell female patient to inform prescriber if she is pregnant.
• Advise female patient not to breastfeed while taking drug.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.


A trademark for the drug mefloquine hydrochloride.


The prophylactic agent of choice for preventing malaria in those travelling to areas with drug-resistant Plasmodium falciparum.
Adverse effects
GI tract disturbances, dizziness; at high doses, convulsions, hallucinations.


Mefloquine, see there.


A brand name for MEFLOQUINE.
References in periodicals archive ?
The US military ceased using Lariam several years ago but inexplicably the Defence Forces here continue to use it.
service members had been diagnosed with permanent brain stem damage caused by Lariam, and Senator Dianne Feinstein, D-California, in a letter to Health and Human Services Secretary Tommy Thompson, said the drug has "serious risks" that have not been adequately tracked by the Pentagon, the Peace Corps and other government agencies that distribute it.
She had explained to them that she ``felt strange'' and was physically ill after taking just two Lariam tablets.
Mr Brunt told the inquest there was a need for a link in law to be established between Lariam and illnesses which could lead to suicide.
Dr Byrne said: "In areas where malaria is resistant, such as Africa, Lariam may still be the best choice.
But this is a relatively rare problem, and most people have no difficulty with Lariam.
They discovered months later that the package insert for Lariam (the ethical equivalent and dated 17 January 1997) included warnings of insomnia and sleep disorders as well as flagging 'toxic encephalopathy of unknown etiology during prophylaxis'.
NEW YORK, March 26 /PRNewswire/ -- More than 300 travelers in the United Kingdom are planning a class action suit against Roche, the manufacturer of Lariam -- the most widely prescribed drug in the world for the prevention of drug-resistant malaria in travelers -- reports the latest issue of Conde Nast Traveler magazine, on newsstands today.
In December 2000, he was on anti- depressants, but he was also prescribed the anti-malaria drug Lariam which is known to cause serious psychiatric side-effects in one in 140 people.
Her parents, who have another daughter, Estelle, 24, said they will not be suing Roche, manufacturers of anti-malaria drug Lariam.
Lariam (mefloquine) is more effective against increasingly resistant strains, but can cause side effects.